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## Pythagorean Identity

Watch the animation below to see how the Pythagorean Identity is really just the Pythagorean Theorem.

Use these flashcards to recognize the Pythagorean Identity. The flashcards use (*x*) instead of θ because the JavaScript for the flashcards does not like the code for θ.

^{sin (x)}/_{sin2 x + cos2x}=**=**^{sin (x)}/_{1}= sin (x)^{ sin2 x+ cos2x }/_{sin x }=**=**^{1}/_{sin x}= csc (x)- 1 - sin
^{2}(x) == cos^{2}(x) - 1 - cos
^{2}(x) == sin^{2}(x)

## Tangent Identity

We call it the Tangent Identity. It’s really just one of a bunch of plain old trig identities. But standardized tests like to slip it in.