# Trigonometric Functions Examples

#### Pythagorean Theorem

A long time ago, when philosophy ruled and Socrates drank hemlock, a brainiac named Pythagoras proved that for right triangles:a2 + b2 = c2Subsequent admirers and right-angle folks know th...

#### Trigonometric Ratios

Sin, Cos, TanWe've had our fun with triangles and legs, Pythagoras and his invention, and exponentials and square roots. But seriously, that stuff isn't at the core of trig.Real trig rocks to the t...

#### The Unit Circle

The unit circle sounds so techno—like moon unit, parental unit—but it's not. Really. It's just a simple little circle with a radius of 1. What's the big deal?It's a useful unit, that's what....

#### Periodic Functions

When a function has values that repeat and repeat over and over (like Macbeth and his obsession with tomorrow and tomorrow and . . .), it's a periodic function.

#### Inverse Functions

Inverse trig functions are sort of like bizarro trig functions. They probably were meant to live in a parallel universe, but somehow they ended up here. Now we're stuck with them. We guess we shoul...

#### Trigonometric Identities

Prove Pythagorean IdentityThe Pythagorean Identity states that sin2ɵ + cos2ɵ = 1 Remember Pythagoras? He's the old dead guy that loved triangles. From the figure below:Now, we can take this info...