Did I answer these correctly?

1.f(x) = 2x + 3
g(x)= 2x^2 + 2x
Find f(g(x) )
2(2x^2+2x)+3
=4x(x+1)+3
= 4x^2+4x+3

2. f(x) = 5x + 3
g(x) = 2x^2-2x + 2
Find (fg(x) )
(5x+3)(2x^2-2x+2)
2(5x+3)(x^2-x+1)
10x^3-4x^2+4x+6

3.f(x)=3x
g(x)= -2x^2 -2x
Find (f - g)(x)
3x-(-2x^2-2x)
=3x+2x^2+2x
=2x^2+5x

4.f(x)=3x + 1
g(x)=x^2-5x -2
Find g(f(x) )
(3x+1)^2-5(3x+1)-2
=6x+1+9x^2-15x-5-2
=9x^2-9x-6

1. agree

2. agree
3. agree
4. agree