Function Problem

Question

Suppose that the functions g and h are defined for all real numbers x as follows.

 

g(x)=2x+3

h(x)=4x

 

Write the expressions for (g+h)(x) and (g-h)(x) and evaluate (g•h)(-1)

Answer 1

Hi Colin,

 

For (g+h) (x) = g(x) + h(x)

 

2x + 3 + 4x = 6x + 3

 

For (g-h) (x) = g(x) - h(x)

 

2x + 3 - 4x = -2x + 3

 

For (g h) (x) = g(h(x))

 

2(4x) + 3 = 8x + 3 = 8(-1) + 3 = -5

 

Good luck.