Algebra 2: Resources and Extra Practice - 9.04 Pythagoras, Trigonometry, and Quadrants

Algebra 2: Resources and Extra Practice

9.04 Pythagoras, Trigonometry, and Quadrants

Essential Question:

How can the Pythagorean Identity be used to

Lesson 9.04 Video - If the video does not load correctly, Click Here to watch the video.

Khan Academy Resources

Intro to the Pythagorean trig identitySal introduces and proves the identity (sinθ)^2+(cosθ)^2=1, which arises from the Pythagorean theorem!

Using the Pythagorean trig identityThe Pythagorean identity tells us that no matter what the value of θ is, sin²θ+cos²θ is equal to 1. This follows from the Pythagorean theorem, which is why it's called the Pythagorean identity! We can use this identity to solve various problems.

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