📘 trigonometry, geometry

1. **Prove the trigonometric identity:** Given: $$(\sin \theta + \cos \theta)^2 = 1 + 2 \sin \theta \cos \theta$$

1. Problem 1 statement: Given that $\sin\theta=5/13$ and $\theta$ is acute, find $\tan\theta$, $\csc\theta$, $\sin\theta$, $\cos\theta$, and $\cot\theta$. 2. Formula and rules: By