Trig Proof 3

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Taught by YourMathGal
  • Currently 4.0/5 Stars.
2484 views | 1 rating
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Meets NCTM Standards:
Lesson Summary:

This lesson focuses on verifying trigonometric identities using the fundamental and Pythagorean identities. The instructor takes a complex fraction and simplifies it by multiplying the numerator and denominator by the least common multiple of both denominators. The instructor then factors and cancels to get the same answer on both sides. The lesson emphasizes the importance of keeping in mind where you're trying to end up as you work through the problem.

Lesson Description:

Shows steps for proving (or verifying) Trigonometric Identities;

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Questions answered by this video:
  • How do you verify / prove trig identities?
  • How do you prove that (csc(x) + cot(x))/(tan(x) + sin(x)) = cot(x)*csc(x)?
  • What are some fundamental trig identities that you need to know to prove trig formulas?
  • What are the Pythagorean identities for trigonometry?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson goes through another more complicated trig identity proof. There are a couple of tricks that you can use to make the left side look like the right side. The more proofs you do, the easier they become. This is another great example of how to go about proving a trig identity.