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Sum and Difference Trigonometric Formulas
These formulas explain how to add and subtract trigonometric functions (and their arguments). If you've got sum time, see what a difference these formulas will make for your trig toolkit.
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Concept Quizzes
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by Brilliant Staff
If \(\sin \theta = \frac{1}{3},\) what is \(\sin 3\theta?\)
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What is \(6\times\left(\frac{3\times\tan10^{\circ}-\tan^3 10^{\circ}}{1-3\times\tan^2 10^{\circ}}\right)^2?\)
Excel in math and science
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If \(\frac{\sin3\theta}{\cos3\theta+2\cos\theta}=7,\) what is the value of \(\tan\theta?\)
Excel in math and science
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It's hard to learn from lectures and videos
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If \(\frac{\sin3\theta}{\cos3\theta+2\cos\theta}=4,\) what is the value of \(\tan\theta?\)
Excel in math and science
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by Brilliant Staff