Given f(x)=5x^2-4 and g(x)=6-1/2x^2, find the expressions
a.) (f o g)(4)

Question

Given f(x)=5x^2-4 and g(x)=6-1/2x^2, find the expressions
a.)  (f o g)(4)

avi13 · Answer

178306/1024=174.12

chrisss · Answer

@avil13 how did you get that

avi13 · Answer

put g(x) in place of x in f(x)
then put value of x=4

3mar · Answer

@avi13
It is not helpful for you to deliver the answers without showing up and proving how they could be figured out!

avi13 · Answer

okk

chrisss · Answer

@3mar if you can show me step my step that would be helpful too

3mar · Answer

Yes, of course!

Do you know what (f o g)(x) means?

chrisss · Answer

@3mar Not really sure, I know it's a inverse function

3mar · Answer

No, @chrisss!
(f o g)(x) means: f is the function of the function g(x).
i.e: g(x) is included in the function f(x).
i.e: replace every x in the function f(x) and put "g(x)" as it is instead of x.

Let's try??

chrisss · Answer

So when he mentioned that I have to substitute the x in f(x) as the function of g how do I do that?

3mar · Answer

Let me show you!!
|dw:1480621809593:dw|

and simplify it now