中等MATH-FUNC-011
Which equation is the reflection of y = f(x) in the x-axis?
A. y = −f(x)✓ 答案
B. y = f(−x)
C. y = f(x) − 1
D. y = |f(x)|
解說
Changing the sign of the output reflects the graph in the x-axis. y = f(−x) reflects in the y-axis. The absolute value folds negative outputs up, which is not a reflection of the whole graph.