Question

Which description matches the transformations y = cosx undergoes to
produce y = 3 cos(-2) ?​

Answer 1

D. Horizontal compression by a factor 2, reflection across the y-axis, then vertical stretch by a factor 3

Explanation:

Given a function f(x)

• f(k*x), where k > 1, horizontal compress it by a factor k

• f(-x) reflect it across the y-axis

• k*f(x), where k > 1, vertical stretch it by a factor k