Question

Consider the function ƒ(x) = (x + 1)2 – 1. Which of the following functions stretches ƒ(x) vertically by a factor of 4?

A) ƒ(x) = 1∕4(x + 1)2 – 4
B) ƒ(x) = (1∕4x + 1)2 + 3
C) ƒ(x) = 4(x + 1)2 – 1
D) ƒ(x) = 4(4x + 1)2 – 1

Answer 1

C f(x) = 4(x+1)2-1

Explanation:

factor of 4 = 2^2

(x+1)2-1 = 4(x+1) 2-1 = with x

= 4(+1) 2-1 = without x

= (4 - 4) 2 = individual products of -1

= (8 - 8 ) = individual products of 2

= 8 - 8 = 2^2 -2^2

= 2^2 - 2^2

(x+1)2-1 = 4(x+1)2-1 = with x

= 2x^2 -2^2

-x = 2^2 -2^2

x = -2^2-2^2

x = 4

which proves f(x) is a factor of 4