Describe the transformations required to obtain the graph of the function f(x) from the graph of the function g(x).
-$$f ( x ) = - 9.5 \sin x ; g ( x ) = \sin x$$
A) Vertical stretch by a factor of $9.5$, reflection across $y$-axis
B) Horizontal stretch by a factor of $9.5$, reflection across $x$-axis
C) Vertical stretch by a factor of $9.5$, reflection across $x$-axis
D) Horizontal stretch by a factor of $9.5$, reflection across $\mathrm { y }$-axis

Question

Quizplus · Accepted Answer

The coefficient $-9.5$ in front of $\sin x$ indicates a vertical stretch by a factor of $9.5$ and a reflection across the $x$-axis, because multiplying by a negative number reflects the graph across the $x$-axis, not the $y$-axis.

Describe the Transformations Required to Obtain the Graph of the Function