what is the period of the function f(x) = cos 10x?\no 5π\no π/5\no 10\no 1/5

Explanation:

Step1: Recall period - formula

For the cosine function $y = A\cos(Bx + C)+D$, the period $T$ is given by $T=\frac{2\pi}{|B|}$.

Step2: Identify the value of B

In the function $f(x)=\cos(10x)$, $B = 10$.

Step3: Calculate the period

Substitute $B = 10$ into the period - formula $T=\frac{2\pi}{|B|}$, we get $T=\frac{2\pi}{10}=\frac{\pi}{5}$.

Answer:

B. $\frac{\pi}{5}$