Trig Identities

$$\sin^2\theta+\cos^2\theta$$

$$1$$

$$1+\tan^2(\theta)$$

$$\sec^2(\theta)$$

$$1+\cot^2\theta$$

$$\csc^2\theta$$

$$\sin^2\theta$$

$$\frac{1-\cos\left(2\theta\right)}{2}$$

$$\cos^2\theta$$

$$\frac{1_{}+\cos^{}\left(2\theta\right)}{2}$$

$$\sqrt{a^2-x^2}$$

$$x=a\sin\theta$$

$$\sqrt{x^2+a^2}$$

$$x=a\tan\theta$$

$$\sqrt{x^2-a^2}$$

$$x=a\sec\theta$$

$$\int_0^{\infty}\!\sec^2\theta\,d\theta$$

$$\tan\theta+C$$

$$\int_0^{\infty}\!\csc^2\,d\theta$$

$$-\cot\theta+C$$

$$\int_0^{\infty}\!\tan\theta\,d\theta$$

$$\ln\vert\sec\theta\vert+C_{}$$

$$\int_0^{\infty}\sec\theta\,d\theta$$

$$\ln\vert\sec\theta+\tan\theta\vert+C$$