Videos and lessons to help High School students learn how to prove the Pythagorean identity sin2(θ) + cos2(θ) = 1 and use it to find sin(θ), cos(θ), or tan(θ) given sin(θ), cos(θ), or tan(θ) and the quadrant of the angle.
Common Core: HSF-TF.C.8
Informal proof and applications of the Pythagorean Identity, that sin2
(θ) + cos2
(θ) = 1.
Pythagorean trig identity from unit circle.
Examples using Pythagorean identities to simplify trigonometric expressions.
Using the Pythagorean trig identity.
Finding exact values using Pythagorean Identity.
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