Question

Suppose that the functions s and t are defined for all real numbers x as follows.

s(x)=2x-2
t(x)=3x
Write the expressions for (s-t)(x) and (s+t)(x) and evaluate (s⋅t)(-1)

Answer 1

(s-t)(-1) = -1

(s+t)(-1) = -7

Explanation:

Given the following set of functions

s(x)=2x-2

t(x)=3x

(s-t)(x) = s(t) - t(x)

(s-t)(x) = 2x - 2 - 3x

(s-t)(x) = -x -2

(s-t)(-1) = -(-1) - 2

(s-t)(-1) = 1-2

(s-t)(-1) = -1

(s+t)(x) = s(t) + t(x)

(s+t)(x) = 2x - 2 + 3x

(s+t)(x) = 5x -2

(s+t)(-1) = 5(-1) - 2

(s+t)(-1) = -5-2

(s+t)(-1) = -7