SOLUTION: I have a question that states: find f(-2) for the function f(x)=2^4x-1

Algebra ->  Functions -> SOLUTION: I have a question that states: find f(-2) for the function f(x)=2^4x-1      Log On


   

Question 87832: I have a question that states: find f(-2) for the function f(x)=2^4x-1
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
I'm not sure whether you meant the problem to be find f(-2) given that
.
f%28x%29+=+2%5E%284x-1%29 <=== first case
.
or
.
f%28x%29+=+2%5E%284x%29+-+1 <=== second case
.
In either case, the way you work this problem is to substitute -2 for x and calculate the
answer.
.
In the first case, substituting -2 for x results in:
.

.
In the second case, substituting -2 for x results in:
.

.
[Note that in these two problems 2%5E9+=+512 and 2%5E8+=+256]
.
Hope this helps you to see your way through the problem. Just remember that when you
write f(-2) it means substitute -2 for the variable on the right side. So f(5) would
mean substitute +5 for the variable, and so forth.