Problema Solution

Determine the value for ‘a’ and ‘b’ resulting in a vertical stretch, af(x), being equivalent to a horizontal stretch, f(bx), for each of the base graphs, y = x2, y = √x, y = x3, y = 1/x.

Provide the general formula for each and one numerical example.

Answer provided by our tutors

af(x)= f(bx)


y = f(x)


For y = x^2


a*x^2 = (bx)^2


ax^2 = b^2x^2


a = b^2


For y = √x


a*√x = √bx


a = √b


For y = x^3


a*x^3 = (bx)^3


a = b^3


For y = 1/x


a*(1/x) = 1/(bx)


a = 1/b


The general formula is a = f(b).