Question

Find f(g(-4)) and g(f(1)) for the pair of functions.

f(x)=x²-4
g(x) = x +3
f(g(-4)) =
g(f(1)) =

Answer 1

(f+g)(x)=f(x)+g(x)

=x

2

+2x+1

(f−g)(x)=f(x)−g(x)

=x

2

−(2x+1)

=x

2

−2x−1

(fg)(x)=f(x).g(x)

=x

2

(2x+1)

=2x

3

+x

2

(

g

f

)(x)=

g(x)

f(x)

(g(x)



=0)

=

2x+1

x

2

(x



=−

2

1

)