00:01
This is problem 1 in chapter 9, section 1.
00:03
In order to do this problem, you will need to reference the table on page 567 of the textbook.
00:09
Problem 1 gives us a multivariable function where w equals f of t comma v, where w is wind chill index, t is actual temperature, and v is wind speed.
00:20
To start with for a, a asks, what is the value of negative 15 for t, comma, 40 for v, and what does this value mean? in order to solve for the value, look at the table for t equals negative 15 and follow it over and match it for b equals 40.
00:38
The value is w equals negative 27.
00:42
So what does this actually mean? it means that if the actual temperature is negative 15 degrees celsius and the wind speed is 40 kilometers per hour, then it would feel subjectively as cold as if it were negative 27 degrees celsius with no wind.
00:56
Now for b, describe the meaning of for what values? value of v is f of negative 20 comma v equal to negative 30 and then solve.
01:06
To solve this one, it'll be very similar.
01:09
Go follow the table down to t equals negative 20 and then look for the value in the table of negative 30 and find out what the v value is according to that.
01:19
V will equal 20...