Write a rule in function notation to describe the transformation that is a reflection across the y-axis.

Question

A.Ry-x(x,y)

B. Rx-0(x,y)

C. Ry-0(x,y)

D. Rx−-1(x,y)

Answer 1

f(-x) is the mirror image reflected across the y-axis of f(x)

(x,y) transforms to (-x,y)

if y=x is the function, the mirror image is y=-x

Just change x to -x wherever it appears in the function

y=x³ - x becomes y=-x³ +x

sometimes there is no difference, as the function includes a reflection of itself, such as f(x)=x² or f(x)=cosx