Question

On a coordinate plane, 2 exponential functions are shown. Function f (x) approaches y = 0 in quadrant 2 and increases into quadrant 1. Function g (x) approaches y = 0 in quadrant 1 and increases into quadrant 2.
Which function represents a reflection of f(x) = Three-eighths(4)x across the y-axis?

g(x) = NegativeThree-eighths (one-fourth) Superscript x
g(x) = Negative three-eighths(4)x
g(x) = Eight-thirds(4)-x
g(x) = Three-eighths(4)–

Answer 1

Reflection across the y-axis: replace x by −x.

f(x) = (3/8)·4^x → g(x) = f(−x) = (3/8)·4^{−x} = (3/8)·(1/4)^x.

So the correct choice is g(x) = (3/8)(1/4)^x (equivalently (3/8)·4^{−x}).