Question

f(x)=4x+1 and g(x)=x^2-5 , find (f o g)(4)

how do I do this??

Answer 1

f(g(x))=f(x^2-5)=4(x^2-5)+1

Answer 2

f(g(4))=4(16-5)+1=4*11+1=45

Answer 3

@Agent47, of course your answer is correct, but as a general policy, we prefer that you lead people to the answer rather than laying it all out at once.

Answer 4

@JamesJ as far as I can tell, this place hasn't changed a bit, and almost nobody ever leads people to the answer rather than laying it all out at once.

Answer 5

Well, you can be part of the difference then!

Answer 6

@SantanaG another method is to find g(4) first. what do you think is g(4)?

Answer 7

g(4)= 4^2-5 =11

Answer 8

correct. now find f(11)

Answer 9

4(11)+1=45

Answer 10

that's the other method :)

Answer 11

oh wow that was easy!! thank you @lgbasallote

Answer 12

hehe lol. just make sure you dont get confused with using that :) it can sometimes get tricky