Question

Find the range of the function $f\left(x\right)=-7\sin \frac{x}{8}$.

• A. All real numbers greater than or equal to $-7$ and less than or equal to $7$
• B. All real numbers greater than or equal to $-7$ and less than or equal to $70$
• C. All real numbers greater than or equal to $0$ and less than or equal to $8$
• D. All real numbers greater than or equal to $0$ and less than or equal to $\frac{1}{8}$
• E. All real numbers greater than or equal to $-\frac{1}{8}$ and less than or equal to $\frac{1}{8}$

Answer 1

The correct option is A All real numbers greater than or equal to $-7$ and less than or equal to $7$

The range of $\sin$ function is $[-1,1]$

Hence multiplying by 7 only makes the range $[-7,7]$