Learn how to solve proving trigonometric identities problems step by step online. Prove the trigonometric identity tan(20)/sin(20)-sec(20)=0. Starting from the left-hand side (LHS) of the identity. Applying the tangent identity: \displaystyle\tan\left(\theta\right)=\frac{\sin\left(\theta\right)}{\cos\left(\theta\right)}. Divide fractions \frac{\frac{\sin\left(20\right)}{\cos\left(20\right)}}{\sin\left(20\right)} with Keep, Change, Flip: \frac{a}{b}\div c=\frac{a}{b}\div\frac{c}{1}=\frac{a}{b}\times\frac{1}{c}=\frac{a}{b\cdot c}. Simplify the fraction \frac{\sin\left(20\right)}{\cos\left(20\right)\sin\left(20\right)} by \sin\left(20\right).

Prove the trigonometric identity tan(20)/sin(20)-sec(20)=0