The Angle Addition Identities were derived using $\sin\theta \equiv \frac{opp}{hyp}$ and $\cos\theta \equiv \frac{adj}{hyp}$. In addition, $\theta$ […]

# Latest Blogs

## The Pythagorean Theorem and the Unit Circle

This following diagram shows that $\displaystyle \sin^2 \theta + \cos^2 \theta = 1$, given $ […]

## Double Angle Formulas

In the Angle Addition Identities post it was shown that $ \displaystyle \sin(x+y) = \sin x \cos […]

## The sine function divided by its angle, and a certain limit

What is $ \lim_{x\rightarrow0} \frac{\sin x}{x}$ ? Recall the definition of a limit, repeated here for reference […]