B. Diketahui fungsi-fungsi f(x)=2x-3

Jawaban:

a.

(fog)(x)=f(g(x))

=f(x²+1) –> f(x)=2x-3

=2(x²+1)-3

=2x²+2-3

=2x²-1

b.

(gof)(x)=g(f(x))

=g(2x-3) –> g(x)=x²+1

=(2x-3)²+1

=4x²-12x+9+1

=4x²-12x+10

c.

(fog)(2)=2x²-1

=2(2)²-1

=2(4)-1

=8-1

=7

d.

(gof)(1)=4x²-12x+10

=4(1)²-12(1)+10

=4-12+10

=2