Question

For f(x) = 3x + 4 and g(x) = x - 1. Calculate (f o g)(x).

For f(x) = 3x + 2 and g(x) = x². Calculate (f o g)(-2).

Consider the function. f(x)= -2x+1. Find the inverse of f(x).

Please help! How do I solve this?

Answer 1

f of g= 3(x-1)+4=3x+1
f of g = 3(-2^2)+2=14

f(x)=-2z+1
y=-2x+1
2x=-y+1
x= -y/2+1/2
finverse= -x/2+1/2

Answer 2

Can you somewhat explain how you got 1 and 2,Im trying to understand D:

Answer 3

wouldn't that be -10?

Answer 4

(f o g)(x) is defined as f(g(x))
so
f(g(x)) = f(x-1) , remember f(x) = 3x+4
f(g(x)) = 3(x-1) + 4 = 3x + 1 , same as bob

or f(g(x))
= 3g(x) + 4
= 3(x-1) + 4 = 3x + 1 , like bob had

in #2
(f o g)(-2)
= f(g(-2)) ----> g(-2) = (-2)^2 = 4
= f(4)
= 3(4) + 2 = 14

last one:
Here is how I do these:
y = -2x + 1
step#1: interchange the x and y variables
x = -2y + 1
step#2: solve this new equation for y
2y = -x + 1
y = (-1/2)x + 1/2 or as bob had it: y = -x/2 + 1/2