lesson
Using Subtraction Formulas to Evaluate Trigonometric Expressions
Evaluate expressions like sin(15°) or cos(15°) by decomposing the angle into a difference of known special angles and applying subtraction formulas.

Evaluate expressions like sin(15°) or cos(15°) by decomposing the angle into a difference of known special angles and applying subtraction formulas.
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10th Grade · Math · CCSS
11 lessons
Prove and apply the addition and subtraction formulas for sine, cosine, and tangent, and use them to derive and apply the double angle formulas.