Given a function ƒ, which of the following represents a vertical stretch by a factor of 3?

(A) y = ƒ(3x)
(B) y = ƒ(x/3)
(C) y = 3ƒ(x)
(D) y = ƒ(x)/3
(E) y = ƒ(x)+ 3

Anonymous Anonymous answered

c