Question

Determine the minimum value of the function f(x)=4^x -8.
I found the derivative f'(x)-4^x ln4. Would I do f'(x)=0 and solve for x?

Answer 1

\[4^{x} -8\]

Answer 2

yes, f'(x) = 0
gives you extreme points

Answer 3

Ok I did that and got 0=4^x ln4 and that would turn to 0=4^x. would would i isolate x?

Answer 4

can 4^x ever be = 0 ?

Answer 5

for any value of x ?

Answer 6

nope

Answer 7

then this function does have any minimum :)

Answer 8

Oh ok! thanks!

Answer 9

or you can say, it has a minimum at \(\Large -\infty \)
which is same as saying it does not have a minimum
\(4^{-\infty } = 0 \)

Answer 10

and welcome ^_^