Operations and functions! So confused

[thejaxx]

I don't know what it is, I just can't get my head wrapped around it and the instructor I swear is a robot!

So I'm trying to figure out how to solve somethign like this:

Find g(4) and f(g(4))

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

g(4)=
f(g(4))=

What's an easy way of figuring it out?

 

[HallsofIvy]

I don't know what it is, I just can't get my head wrapped around it and the instructor I swear is a robot!

So I'm trying to figure out how to solve somethign like this:

Find g(4) and f(g(4))

f(x)=x^2-x+1

This says "whatever x is, square it, subtract x from it, and add 1".
for example, f(3)= 3^2- 3+ 1. 3 squared is 9. Subtract x from that to get 6, then add 1: f(3)= 7.
f(5)= 5^2- 5+ 1. 5 squared is 25. Subtract 20 from that to get 20, then add 1: f(5)= 21.

g(x)=4x-2

This says "whatever is, multiply it by 4 then subtract 2". g(3)= 4(3)- 2= 12- 2= 10. g(-1)= 4(-1)- 2= -4- 2= -6. g(7)= 4(7)- 2= 28- 2= 26.

g(4)=

g(4)= 4(4)- 2. What is that?

f(g(4))=

What ever number you got above, square it, subtract it from that square, the subtract 1.

What's an easy way of figuring it out?[/QUOTE]