00:01
This problem number fifteen of this tour calculus eighth edition, section two point seven.
00:06
The displacement and meters of a particle moving in a straight line is given by the equation of motion as equals one over t squared ortiz measured in seconds.
00:15
Find the velocity of the particle times t equals a tickles.
00:18
One tickles too and t equals three.
00:22
So for this for this problem, the position functioned.
00:26
The displacement is given here we know dysfunction.
00:30
The velocity will be the slope of this function of slope function.
00:34
I mean, we'll use definition one where are slow.
00:39
We're gonna call our velocity and its element as t approaches a this is the first part we're going to do thi is equal today parties of progeny out of the function f fifty minus the function evaluated a today divided by the difference of tina our function f ft is given as one over t squared and dysfunction.
01:10
Evaluated a is one of a squared all over eighteen minutes saying we can get rid of the functions in the numerator by multiplying by the that was common denominator, which is? he scored a squared.
01:25
So we're gonna want to apply that to the top of the bottom t squared a squared multiplied by the first term.
01:31
Just he was in a squared.
01:34
He scored a squared multiplied by the second term just leaves a t's great! and in the denominator we'll have this term t minus saying, provided by this t squared a squirter.
01:48
Our next step is too factor thie greater.
01:53
It's a difference of squares, meaning that hey, screw my c squared is the same as a minus.
01:59
Team a plus team on the right, by the quantity t minus a ah t squared a squared.
02:15
Now we can cancel here we can replace a minus t with negative team, anything that's equivalent, and then we can cancel team and with t minus a.
02:29
Those two terms are equivalent as t approaches a and we're left with negative...