Question

Given that f(x)=x^2-8 and g(x)=4-x, find (f-g)(-1) , if it exists.

Answer 1

We have the following data:

1. f(x) = x2 - 8

and g(x) = 4-x

We have to find (f-g)

So we are going to replace f and g

Then we have:

((x2-8)-(4-x))

= (x2 -8 -4 + x)

= (x2-12+x)

= x2 + x - 12

Now we need to replace the x value by -1 because it is the value that is given on the exercise.

So,

= (-1)^2 + (-1) - 12

= 1 - 1 - 12

= - 12