Applying the tangent identity: $\displaystyle\tan\left(\theta\right)=\frac{\sin\left(\theta\right)}{\cos\left(\theta\right)}$

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

Simplify the fraction $\frac{\sin\left(x\right)\cos\left(x\right)^2}{\sin\left(x\right)}$ by $\sin\left(x\right)$

When multiplying two powers that have the same base ($\cos\left(x\right)$), you can add the exponents

Applying the pythagorean identity: $\sin^2\left(\theta\right)+\cos^2\left(\theta\right)=1$