SOLUTION: I have ran into a synthesis problem that I cannot seem to answer as I feel that the problem has not given me enough information to complete what was given to me as a problem to com

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Question 349556: I have ran into a synthesis problem that I cannot seem to answer as I feel that the problem has not given me enough information to complete what was given to me as a problem to complete. Let +f%28x%29=3x%5E2-1+ and +g%28x%29=2x%2B5+. Find +f%28g%28-1%29%29+ and +g%28f%28-1%29%29+.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
your equations are:

f(x) = 3x^2 - 1

g(x) = 2x + 5

you want to find f(g(-1))

first you have to find g(-1)

since g(x) = 2x + 5, then g(-1) = 2*(-1) + 5 = -2 + 5 = 3

f(g(-1)) becomes f(3) because g(-1) = 3

since f(x) = 3x^2 - 1, then f(3) = 3*(3^2) - 1 = 3*9 - 1 = 27 - 1 = 26

solve for the inner function first and then use that value to solve for the outer function.

you want to solve for g(f(-1))

since f(x) = 3x^2 - 1, then f(-1) = 3*(-1)^2 - 1 = 3 - 1 = 2

since g(x) = 2x + 5, then g(f(-1)) = g(2) = 2*2 + 4 = 4 + 5 = 9