Consider the function f(x). Select all of the following that include a vertical stretch of f(x)

A. -2f(x)
B. 0.25f(x)
C. -f(x) + 6
D. 5.5f(x) - 1
E. f(x) + 9
F. 7f(x)

A, D and F.

Step-by-step explanation:

If f(x) is a function and another function is defined as

If |k|>1, then it is clear vertical stretch.

If 0<|k|<1, then it is clear vertical compression.

In function ,

vertical stretch.

In function ,

vertical compression.

In function ,

neither stretch nor compression.

In function ,

vertical stretch.

In function ,

neither stretch nor compression.

In function ,

vertical stretch.

Hence, the correct options are A, D and F.