Question

PLEASE HELP!!!!!!!

For f(x) = 4x + 3 and g(x) = 9x find the following composite functions and state the domain of each
(a) f o g (b) g o f (c) f o f (d) g o g
(a) (f o g)(x) =

Answer 1

Explanation:

For f(x) = 4x + 3 and g(x) = 9x

(a) (f o g) (x)

= f (g (x))

= f (9x)

= 4(9x) +3

= 36x + 3

Its domain is any real number.

(b) (g o f) (x)

= g (f (x))

= g (4x + 3)

= 9 (4x + 3)

= 36x + 27

Again its domain is any real number.

(c) (f o f) (x)

= f (f (x))

= f (4x + 3)

= 4(4x + 3) + 3

= 16x + 12 + 3

= 16x + 15

Again its domain is any real number.

(d) (g o g) (x)

= g ( g (x))

= g (9x)

= 9(9x)

= 81x

Again its domain is any real number.

Answer 2

solution given:

f(x) = 4x + 3

g(x) = 9x

answer:

a.fog(x)=f(9x)=4×9x+3=36x+3

domain=real number

b.gof (x)=g(4x+3)=9(4x+3)=36x+26

domain=real number

c.fof(x)=f(4x+3)=4(4x+3)+3=16x+12+3

=16x+15

domain: real number

d.

gog(x)=g(9x)=9×9x=81x

domain: real number.