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Geometry
Sum and Difference Trigonometric Formulas
Excel in math and science
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Concept Quizzes
Using the cosine difference formula, what is the value of
\[ \cos 15 ^ \circ ?\]
Excel in math and science
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by Brilliant Staff
Which of the following is equal to
\[ \cos 56 ^ \circ \cos 11 ^ \circ + \sin 56 ^ \circ \sin 11 ^ \circ ? \]
Excel in math and science
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Which of the following is equal to
\[ \cos 15 ^ \circ \cos 45 ^ \circ - \sin 15 ^ \circ \sin 45 ^ \circ ?\]
Excel in math and science
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Which of the following is NOT equal to \( \cos 2 \theta \)?
Excel in math and science
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\(N\) and \(M\) are real numbers such that
\[ \cos ( \alpha + \beta) = N \cos \alpha \cos \beta + M \sin \alpha \sin \beta \]
is an algebraic identity. What is the value of \(N+M\).
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
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That seems reasonable.
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by Brilliant Staff