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Applied Calculus for the MLSS A Brief Approach

Soo T. Tan

Chapter 3

Differentiation - all with Video Answers

Educators


Section 1

Basic Rules of Differentiation

01:23

Problem 1

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=-3$$

Wendi Zhao
Wendi Zhao
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01:17

Problem 2

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=365$$

Wendi Zhao
Wendi Zhao
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00:55

Problem 3

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=x^{5}$$

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00:53

Problem 4

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=x^{7}$$

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01:00

Problem 5

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=x^{3.1}$$

Wendi Zhao
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01:27

Problem 6

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=x^{0.8}$$

Wendi Zhao
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02:08

Problem 7

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=3 x^{2}$$

Wendi Zhao
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01:45

Problem 8

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=-2 x^{3}$$

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02:25

Problem 9

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(r)=\pi r^{2}$$

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02:07

Problem 10

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(r)=\frac{4}{3} \pi r^{3}$$

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02:21

Problem 11

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=9 x^{1 / 3}$$

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02:29

Problem 12

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{5}{4} x^{4 / 5}$$

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Wendi Zhao
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02:11

Problem 13

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=3 \sqrt{x}$$

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02:17

Problem 14

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(u)=\frac{2}{\sqrt{u}}$$

Wendi Zhao
Wendi Zhao
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02:04

Problem 15

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=7 x^{-12}$$

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02:07

Problem 16

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=0.3 x^{-12}$$

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02:12

Problem 17

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=5 x^{2}-3 x+7$$

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01:57

Problem 18

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=x^{3}-3 x^{2}+1$$

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Wendi Zhao
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02:02

Problem 19

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=-x^{3}+2 x^{2}-6$$

Wendi Zhao
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03:00

Problem 20

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\left(1+2 x^{2}\right)^{2}+2 x^{3}$$

Wendi Zhao
Wendi Zhao
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01:53

Problem 21

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=0.03 x^{2}-0.4 x+10$$

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Wendi Zhao
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02:48

Problem 22

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=0.002 x^{3}-0.05 x^{2}+0.1 x-20$$

Wendi Zhao
Wendi Zhao
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02:57

Problem 23

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{2 x^{3}-4 x^{2}+3}{x}$$

Wendi Zhao
Wendi Zhao
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02:19

Problem 24

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{x^{3}+2 x^{2}+x-1}{x}$$

Wendi Zhao
Wendi Zhao
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02:10

Problem 25

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=4 x^{4}-3 x^{5 / 2}+2$$

Wendi Zhao
Wendi Zhao
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03:33

Problem 26

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=5 x^{4 / 3}-\frac{2}{3} x^{3 / 2}+x^{2}-3 x+1$$

Wendi Zhao
Wendi Zhao
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01:41

Problem 27

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=5 x^{-1}+4 x^{-2}$$

Wendi Zhao
Wendi Zhao
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01:59

Problem 28

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=-\frac{1}{3}\left(x^{-3}-x^{6}\right)$$

Wendi Zhao
Wendi Zhao
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02:47

Problem 29

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(t)=\frac{4}{t^{4}}-\frac{3}{t^{3}}+\frac{2}{t}$$

Wendi Zhao
Wendi Zhao
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02:37

Problem 30

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{5}{x^{3}}-\frac{2}{x^{2}}-\frac{1}{x}+200$$

Wendi Zhao
Wendi Zhao
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01:50

Problem 31

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=3 x-5 \sqrt{x}$$

Wendi Zhao
Wendi Zhao
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02:01

Problem 32

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(t)=2 t^{2}+\sqrt{t^{3}}$$

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02:22

Problem 33

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{2}{x^{2}}-\frac{3}{x^{1 / 3}}$$

Wendi Zhao
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02:25

Problem 34

Find the derivative of the function $f$ by using the rules of differentiation.
$$f(x)=\frac{3}{x^{3}}+\frac{4}{\sqrt{x}}+1$$

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Wendi Zhao
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02:40

Problem 35

Let $f(x)=2 x^{3}-4 x .$ Find:
a. $f^{\prime}(-2)$
b. $f^{\prime}(0)$
c. $f^{\prime}(2)$

Wendi Zhao
Wendi Zhao
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03:48

Problem 36

Let $f(x)=4 x^{5 / 4}+2 x^{3 / 2}+x .$ Find:

a. $f^{\prime}(4)$
b. $f^{\prime}(16)$

Wendi Zhao
Wendi Zhao
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02:53

Problem 37

Find each limit by evaluating the derivative of a suitable function at an appropriate point.

$$\lim _{h \rightarrow 0} \frac{(1+h)^{3}-1}{h}$$

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Wendi Zhao
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01:33

Problem 38

Find each limit by evaluating the derivative of a suitable function at an appropriate point.

$$\lim _{x \rightarrow 1} \frac{x^{5}-1}{x-1}$$
Hint: Let $h=x-1$

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03:12

Problem 39

Find each limit by evaluating the derivative of a suitable function at an appropriate point.

$$\lim _{h \rightarrow 0} \frac{3(2+h)^{2}-(2+h)-10}{h}$$

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Wendi Zhao
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03:28

Problem 40

Find each limit by evaluating the derivative of a suitable function at an appropriate point.

$$\lim _{t \rightarrow 0} \frac{1-(1+t)^{2}}{t(1+t)^{2}}$$

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Wendi Zhao
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02:38

Problem 41

Find the slope and an equation of the tangent line to the graph of the function $f$ at the specified point.
$$f(x)=2 x^{2}-3 x+4 ;(2,6)$$

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Wendi Zhao
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03:12

Problem 42

Find the slope and an equation of the tangent line to the graph of the function $f$ at the specified point.

$$f(x)=-\frac{5}{3} x^{2}+2 x+2 ;\left(-1,-\frac{5}{3}\right)$$

Wendi Zhao
Wendi Zhao
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03:37

Problem 43

Find the slope and an equation of the tangent line to the graph of the function $f$ at the specified point.

$$f(x)=x^{4}-3 x^{3}+2 x^{2}-x+1 ;(2,-1)$$

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Wendi Zhao
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04:05

Problem 44

Find the slope and an equation of the tangent line to the graph of the function $f$ at the specified point.

$$f(x)=\sqrt{x}+\frac{1}{\sqrt{x}} ;\left(4, \frac{5}{2}\right)$$

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Wendi Zhao
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02:03

Problem 45

Let $f(x)=x^{3}$
a. Find the point on the graph of $f$ where the tangent line is horizontal.
b. Sketch the graph of $f$ and draw the horizontal tangent line.

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02:41

Problem 46

Let $f(x)=x^{3}-4 x^{2}$. Find the points on the graph of $f$ where the tangent line is horizontal.

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04:29

Problem 47

Let $f(x)=x^{3}+1$
a. Find the points on the graph of $f$ where the slope of the tangent line is equal to 12 .
b. Find the equation(s) of the tangent line(s) of part (a).
c. Sketch the graph of $f$ showing the tangent line(s).

Wendi Zhao
Wendi Zhao
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02:49

Problem 48

Let $f(x)=\frac{2}{3} x^{3}+x^{2}-12 x+6 .$ Find the values of $x$ for which:
a. $f^{\prime}(x)=-12$
b. $f^{\prime}(x)=0$
c. $f^{\prime}(x)=12$

Harsh Gadhiya
Harsh Gadhiya
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05:45

Problem 49

Let $f(x)=\frac{1}{4} x^{4}-\frac{1}{3} x^{3}-x^{2}$. Find the points on the graph of $f$ where the slope of the tangent line is equal to:
a. $-2 x$
b.$ 0$
c. $10 x$

Stark Ledbetter
Stark Ledbetter
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03:26

Problem 50

A straight line perpendicular to and passing through the point of tangency of the tangent line is called the normal to the curve at that point. Find an equation of the tangent line and the normal to the curve $y=x^{3}-3 x+1$ at the point (2,3)

Wendi Zhao
Wendi Zhao
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01:22

Problem 51

The volume of a spherical cancerous tumor is given by the function
$$V(r)=\frac{4}{3} \pi r^{3}$$
where $r$ is the radius of the tumor in centimeters. Find the rate of change in the volume of the tumor with respect to its radius when
a. $r=\frac{2}{3} \mathrm{cm}$
b. $r=\frac{5}{4} \mathrm{cm}$

Edward Downes
Edward Downes
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02:42

Problem 52

The velocity (in centimeters per second) of blood $r \mathrm{cm}$ from the central axis of an artery is given by
$$v(r)=k\left(R^{2}-r^{2}\right)$$
where $k$ is a constant and $R$ is the radius of the artery (see the accompanying figure). Suppose $k=1000$ and $R=0.2 \mathrm{cm} .$ Find $v(0.1)$ and $v^{\prime}(0.1),$ and interpret your results.

Wendi Zhao
Wendi Zhao
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02:38

Problem 53

The number of tablets and smartphones in use worldwide (in millions) in year $t$ from 2010 through 2012 is approximately
$$f(t)=128.1 t^{1.94} \quad(1 \leq t \leq 3)$$
where $t=1$ corresponds to 2010
a. How many tablets and smartphones were in use in $2011 ?$
b. How fast was the number of tablets and smartphones changing in $2011 ?$
Source: MIT Technology Review.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:49

Problem 54

As mobile phones continue to proliferate, more and more people will watch video content on them through a mobile browser, subscription, download, or application at least once a month. In a study released in 2013 , eMarketer estimated that the number of mobile phone video viewers in the United Kingdom in year $t$ from $2011(t=0)$ through $2017(t=6)$ will be
$$P(t)=13.86 t^{0.535}$$
percent of the population.
a. What percentage of the U.K. population is expected to watch video content on mobile phones
in $2015 ?$
b. How fast is the percentage of mobile phone video viewers in the United Kingdom in 2015 expected to change?

Stark Ledbetter
Stark Ledbetter
Numerade Educator
04:39

Problem 55

The percentage of families that were married couples with children between 1970 and 2010 is approximately
$$
P(t)=\frac{49.6}{t^{0.27}} \quad(1 \leq t \leq 5)
$$
where $t$ is measured in decades, with $t=1$ corresponding to $1970 .$
a. What percentage of families were married couples with children in $1970 ?$ In 1990 ? In 2010 ?
b. How fast was the percentage of families that were married couples with children changing in $1990 ?$ In $2000 ?$

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:20

Problem 56

According to data from a General Motors study, the average speed of your trip $A$ (in miles per hour) is related to the number of stops per mile you make on the trip $x$ by the equation
$$
A=\frac{26.5}{x^{0.45}}
$$
Compute $d A / d x$ for $x=0.25$ and $x=2 .$ How is the rate of change with respect to $x$ of the average speed of your trip affected by the number of stops per mile?

Edward Downes
Edward Downes
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02:11

Problem 57

The share of households in the United States that are earning middle-class incomes has been in decline since the 1970 s. The percentage of households with annual incomes within $50 \%$ of the median income is given by
$$
P(t)=50.3 t^{-0.09} \quad(1 \leq t \leq 6)
$$
where $t$ is measured in decades, with $t=1$ corresponding to $1980 .$
a. What percentage of households had annual incomes within $50 \%$ of the median income in 2010?
b. How fast was the percentage of households with annual incomes within $50 \%$ of the median income decreasing in $2010 ?$

Wendi Zhao
Wendi Zhao
Numerade Educator
02:33

Problem 58

The demand function for the Luminar desk lamp is given by
$$p=f(x)=-0.1 x^{2}-0.4 x+35$$
where $x$ is the quantity demanded in thousands and $p$ is the unit price in dollars.
a. Find $f^{\prime}(x)$
b. What is the rate of change of the unit price when the quantity demanded is 10,000 units $(x=10) ?$ What is the unit price at that level of demand?

Chasen Shaw
Chasen Shaw
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01:52

Problem 59

During a test by the editors of an auto magazine, the distance $s$ (in feet) traveled by the MacPherson $X$ - 2 racing car $t$ sec after the brakes were applied conformed to the rule
$$
s=f(t)=120 t-15 t^{2} \quad(t \geq 0)
$$
a. Find an expression for the car's velocity $v$ at any time $t$
b. What was the car's velocity when the brakes were first applied?
c. What was the car's stopping distance for that particular test?
Hint: The stopping time is found by setting $v=0$

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:28

Problem 60

Mobile instant messaging (IM) is a small portion of total IM usage, but it is growing sharply. The function
$$
P(t)=0.257 t^{2}+0.57 t+3.9 \quad(0 \leq t \leq 4)
$$
gives the mobile IM accounts in year $t$ as a percentage of total enterprise IM accounts from 2006 $(t=0)$ through $2010(t=4)$
a. What percentage of total enterprise IM accounts were the mobile accounts in $2008 ?$
b. How fast was this percentage changing in $2008 ?$

Stark Ledbetter
Stark Ledbetter
Numerade Educator
01:51

Problem 61

The average annual medical costs for a family of four in the United States from 2001 through 2011 is approximated by the function
$$
C(t)=22.9883 t^{2}+830.358 t+7513 \quad(1 \leq t \leq 11)
$$
where $t$ is measured in years, with $t=1$ corresponding to 2001 , and $C(t)$ is measured in dollars.
a. What was the approximate average annual medical costs for a family of four in $2010 ?$
b. How fast was the approximate average medical costs for a family of four increasing in $2010 ?$

Wendi Zhao
Wendi Zhao
Numerade Educator
03:36

Problem 62

Based on the current eligibility requirement, a study conducted in 2004 showed that federal spending on entitlement programs, particularly Medicare, would grow enormously in the future. The study predicted that spending on Medicare, as a percentage of the gross domestic product (GDP), will be
$$
P(t)=0.27 t^{2}+1.4 t+2.2 \quad(0 \leq t \leq 5)
$$
percent in year $t,$ where $t$ is measured in decades, with $t=0$ corresponding to $2000 .$
a. How fast was the spending on Medicare, as a percentage of the GDP, growing in $2010 ?$ How fast will it be growing in $2020 ?$
b. What was the predicted spending on Medicare in $2010 ?$ What will it be in $2020 ?$
Source: Congressional Budget Office.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:46

Problem 63

An economy's consumer price index (CPI) is described by the function
$$
I(t)=-0.2 t^{3}+3 t^{2}+100 \quad(0 \leq t \leq 11)
$$
in year $t,$ where $t=0$ corresponds to 2003
a. At what rate was the CPI changing in $2008 ?$ In $2010 ?$ In $2013 ?$
b. What was the average rate of increase in the CPI over the period from

Wendi Zhao
Wendi Zhao
Numerade Educator
02:36

Problem 64

An efficiency study conducted for Elektra Electronics showed that the number of Space Commander walkie-talkies assembled by the average worker during the morning shift $t$ hr after starting work at 8 A.M. is given by
$$
N(t)=-t^{3}+6 t^{2}+15 t \quad(0 \leq t \leq 4)
$$
a. Find the rate at which the average worker will be assembling walkie-talkies $t$ hr after starting work.
b. At what rate will the average worker be assembling walkie-talkies at 10 A.M.? At 11 A.M.?
c. How many walkie-talkies will the average worker assemble between 10 A.M. and 11 A.M.?

Wendi Zhao
Wendi Zhao
Numerade Educator
02:25

Problem 65

Five years ago, the government of a Pacific Island country launched an extensive propaganda campaign aimed toward curbing the country's population growth. According to the Census Department, the population (measured in thousands of people) for the following 4 years was
$$
P(t)=-\frac{1}{3} t^{3}+64 t+3000
$$
where $t$ is measured in years and $t=0$ corresponds to the start of the campaign. Find the rate of change of the population at the end of years $1,2,3,$ and $4 .$ Was the plan working?

Stark Ledbetter
Stark Ledbetter
Numerade Educator
01:42

Problem 66

A certain species of turtle faces extinction because dealers collect truckloads of turtle eggs to be sold as aphrodisiacs. After severe conservation measures are implemented, it is hoped that the turtle population will grow according to the rule
$$
N(t)=2 t^{3}+3 t^{2}-4 t+1000 \quad(0 \leq t \leq 10)
$$
where $N(t)$ denotes the population at the end of year $t$. Find the rate of growth of the turtle population when $t=2$ and $t=8 .$ What will be the population 10 years after the conservation
measures are implemented?

Wendi Zhao
Wendi Zhao
Numerade Educator
03:46

Problem 67

The altitude (in feet) of a model rocket $t$ sec into a trial flight is given by
$$
s=f(t)=-2 t^{3}+12 t^{2}+5 \quad(t \geq 0)
$$
a. Find an expression $v$ for the rocket's velocity at any time $t$
b. Compute the rocket's vertical velocity when $t=0,2,4,$ and $6 .$ Interpret your results.
c. Using the results from the solution to part (b), find the maximum altitude attained by the rocket.
Hint: At its highest point, the velocity of the rocket is zero.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
01:22

Problem 68

The supply function for a certain make of satellite radio is given by
$$
p=f(x)=0.0001 x^{5 / 4}+10
$$
where $x$ is the quantity supplied and $p$ is the unit price in dollars.
a. Find $f^{\prime}(x)$
b. What is the rate of change of the unit price if the quantity supplied is 10,000 satellite radios?

Wendi Zhao
Wendi Zhao
Numerade Educator
01:42

Problem 69

A study prepared for a Sunbelt town's chamber of commerce projected that the town's population in the next 3 years will grow according to the rule
$$
P(t)=50,000+30 t^{3 / 2}+20 t
$$
where $P(t)$ denotes the population $t$ months from now. How fast will the population be increasing 9 months and 16 months from now?

Edward Downes
Edward Downes
Numerade Educator
04:27

Problem 70

The average speed of a vehicle on a stretch of Route 134 between 6 A.M. and 10 A.M. on a typical weekday is approximated by the function
$$
f(t)=20 t-40 \sqrt{t}+50 \quad(0 \leq t \leq 4)
$$
where $f(t)$ is measured in miles per hour and $t$ is measured in hours, with $t=0$ corresponding to 6
A.M.
a. Compute $f^{\prime}(t)$
b. What is the average speed of a vehicle on that stretch of Route 134 at 6 A.M.? At 7 A.M.? At 8
A.M.?
c. How fast is the average speed of a vehicle on that stretch of Route 134 changing at 6: 30 A.M.? At 7 A.M.? At 8 A.M.?

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:20

Problem 71

The relationship between the amount of money $x$ that Cannon Precision Instruments spends on advertising and the company's total sales $S(x)$ is given by the function
$$
S(x)=-0.002 x^{3}+0.6 x^{2}+x+500 \quad(0 \leq x \leq 200)
$$
where $x$ is measured in thousands of dollars. Find the rate of change of the sales with respect to the amount of money spent on advertising. Are Cannon's total sales increasing at a faster rate when the amount of money spent on advertising is
(a) $\$ 100,000$ or
(b) $\$ 150,000 ?$

Stark Ledbetter
Stark Ledbetter
Numerade Educator
03:02

Problem 72

The per capita health spending in the United States in year $t$ for the years 2000 through 2011 is approximately
$$C(t)=-1.1708 t^{3}+7.029 t^{2}+389.69 t+4780 \quad(0 \leq t \leq 11)$$
dollars in year $t,$ with $t=0$ corresponding to $2000 .$
a. What was the per capita health spending in $2010 ?$
b. How fast was the per capita health spending changing in $2010 ?$
Source: NHCM Foundation.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
03:06

Problem 73

The body mass index (BMI) measures body weight in relation to height.
A BMI of 25 to 29.9 is considered overweight, a BMI of 30 or more is considered obese, and a BMI of
40 or more is morbidly obese. The percentage of the U.S. population that is obese is approximated by the function
$$
P(t)=0.0004 t^{3}+0.0036 t^{2}+0.8 t+12 \quad(0 \leq t \leq 20)
$$
where $t$ is measured in years, with $t=0$ corresponding to the beginning of $1991 .$
a. What percentage of the U.S. population was deemed obese at the beginning of $1991 ?$ At the beginning of $2010 ?$
b. How fast was the percentage of the U.S. population that is deemed obese changing at the beginning of 1991? At the beginning of 2010?
(Note: A formula for calculating the BMI of a person is given in Exercise 35.)
Source: Centers for Disease Control and Prevention.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
03:01

Problem 74

The population age 65 and over (in millions) of developed countries from 2005 through 2034 is projected to be
$$
f(t)=3.567 t+175.2 \quad(5 \leq t \leq 35)
$$
where $t$ is measured in years and $t=5$ corresponds to $2005 .$ On the other hand, the population age
65 and over of underdeveloped/emerging countries over the same period is projected to be
$$
g(t)=0.46 t^{2}+0.16 t+287.8 \quad(5 \leq t \leq 35)
$$
a. What does the function $D=g+f$ represent?
b. Find $D^{\prime}$ and $D^{\prime}(10),$ and interpret your results.
Source: U.S. Census Bureau, United Nations.

Stark Ledbetter
Stark Ledbetter
Numerade Educator
06:17

Problem 75

- Shortage of Nurses The projected number of nurses (in millions) in year $t$ from 2000 through 2015 is given by
$$
N(t)=\left\{\begin{array}{ll}
1.9 & \text { if 0 } \leq t<5 \\
-0.0004 t^{2}+0.038 t+1.72 & \text { if 5 } \leq t \leq 15
\end{array}\right.
$$
where $t=0$ corresponds to 2000 . The projected number of nursing jobs (in millions) over the same period is
$$
J(t)=\left\{\begin{array}{ll}
-0.0002 t^{2}+0.032 t+2 & \text { if } \leq t < 10 \\
-0.0016 t^{2}+0.12 t+1.26 & \text { if } 10 \leq t \leq 15
\end{array}\right.
$$
a. Find the rule for the function $G=J-N$ giving the gap between the supply and the demand of nurses from 2000 through $2015 .$
b. How fast was the gap between the supply and the demand of nurses changing in 2008 ? In $2012 ?$
Source: U.S. Department of Health and Human Services.

Wendi Zhao
Wendi Zhao
Numerade Educator
01:24

Problem 76

Determine whether the statement is true or false. If it is true, explain why it is true. If it is false, give an example to show why it is false.
If $f$ and $g$ are differentiable, then
$$\frac{d}{d x}[2 f(x)-5 g(x)]=2 f^{\prime}(x)-5 g^{\prime}(x)$$
True False

Wendi Zhao
Wendi Zhao
Numerade Educator
01:54

Problem 77

Determine whether the statement is true or false. If it is true, explain why it is true. If it is false, give an example to show why it is false.
If $f(x)=\pi^{x},$ then $f^{\prime}(x)=x \pi^{x-1}$

Stark Ledbetter
Stark Ledbetter
Numerade Educator
02:43

Problem 78

Prove the Power Rule (Rule 2 ) for the special case $n=3$.
Hint: Compute $\lim _{h \rightarrow 0}\left[\frac{(x+h)^{3}-x^{3}}{h}\right]$

Wendi Zhao
Wendi Zhao
Numerade Educator