OpenStax, Algebra and Trigonometry 2e §9.2 Sum and Difference Identities · Example 3 · Trigonometry · Compound & multiple angles

Using Sum and Difference Identities to Evaluate the Difference of Angles

Use the sum and difference identities to evaluate the difference of the angles and show that part a equals part b.

ⓐ $s in (45° - 30°)$
ⓑ $s in (135° - 120°)$

~5 minWritten answer · check your work with Lemma

OpenStax, Algebra and Trigonometry 2e · §9.2 Sum and Difference Identities · Example 3

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