Divide fractions $\frac{\cos\left(\theta\right)}{\frac{1}{\cos\left(\theta\right)}}$ with Keep, Change, Flip: $a\div \frac{b}{c}=\frac{a}{1}\div\frac{b}{c}=\frac{a}{1}\times\frac{c}{b}=\frac{a\cdot c}{b}$

Combine all terms into a single fraction with $\cos\left(\theta\right)$ as common denominator

When multiplying exponents with same base you can add the exponents: $\cos\left(\theta\right)^2\cos\left(\theta\right)$

Add the values $2$ and $1$