Determine the amplitude or period as requested.
-Period of $y = \frac { 9 } { 8 } \cos \frac { 4 \pi } { 7 } x$
A) $\frac { 7 } { 2 }$
B) $\frac { 8 \pi } { 7 }$
C) $\frac { 9 \pi } { 4 }$
D) $\frac { 4 } { 9 }$

Question

Quizplus · Accepted Answer

The period of a cosine function $y = a \cos(bx)$ is given by $\frac{2\pi}{b}$. Here, $b = \frac{4\pi}{7}$, so the period is $\frac{2\pi}{\frac{4\pi}{7}} = \frac{7}{2}$.

Determine the Amplitude or Period as Requested y=98cos⁡4π7xy = \frac { 9 } { 8 } \cos \frac { 4 \pi } { 7 } xy=89​cos74π​x

Determine the Amplitude or Period as Requested $y = \frac { 9 } { 8 } \cos \frac { 4 \pi } { 7 } x$