$\"\"$

The function is $\"\"$ .

Find how many zeros does the above function have in the interval $\"\"$ .

The general form of cos function is $\"\"$ .

The function $\"\"$ ,therefore $\"\"$

Period $\"\"$

Substitute $\"\"$ in the above function .

Period $\"\"$ .

The function $\"\"$ completes one cycle in the interval $\"\"$ .

The cosine function have two zeros in one complete cycle.

Therefore cosine function have two zeros in the interval $\"\"$ .

The cosine function have $\"\"$ cycless in the interval $\"\"$ .

In every cycle cosine function has two zeros ,hence total number of zeros in the interval $\"\"$ of the function $\"\"$ is $\"\"$ .

$\"\"$

$\"\"$ zeros.