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# Fundamental Trigonometric Identities

These are your basic building blocks for solving trigonometric equations and understanding how the pieces fit together. Using these identities can make sense of even the scariest looking trig.

# Trigonometric Periodicity Identities

Which of the following is equal to $$3\cos(11\pi+x)?$$

Which of the following is equal to $$2\tan\left(x-\frac{5}{2}\pi\right)?$$

Which of the following is equal to $\sin^2(5\pi+x)+\cos^2(-4\pi-x)+\tan^2\left(\frac{5}{2}\pi+x\right)$ for a random $$x?$$

Find the value of $$\sin\left(-\frac{5}{3}\pi\right)+\cos\left(\frac{59}{6}\pi\right)+\tan\left(\frac{31}{3}\pi\right).$$

Which of the following is equal to $$\sin\left(\frac{39}{2}\pi+3x\right)?$$

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