Simplify the expression.
${\tan }^2\theta -{\sec }^2\theta +1$

Select the expression with the same value as the given expression.

$\sec (-\frac{4\pi }{5})$

Select the expression with the same value as the given expression.

$\sin (-38°)$

Use the Pythagorean identities to rewrite the expression as a single term.

$(1+\csc \theta )(1-\csc \theta )$

Use the Pythagorean identities to rewrite the expression with no fraction.

$\frac{1}{1-\sec \theta }$

Simplify the expression.

$\frac{\tan (-\theta )}{\sec (-\theta )}$

Simplify the expression.

$(\frac{{\tan }^2\theta }{{\sin }^2\theta }-1){\csc }^2\left(\theta \right){\cos }^2(-\theta )$

Identify the most helpful first step in verifying the identity.

$(\frac{{\tan }^2\theta }{{\sin }^2\theta }-1)={\sec }^2\theta {\sin }^2(-\theta )$

Identify the most helpful first step in verifying the identity.

${\sec }^3\theta =\sec \theta +\frac{{\tan }^2\theta }{\cos \theta }$