Prove the Identity $\cos 3 x=\cos ^{3} x-3 \sin ^{2} x \cos x$

question 10

Essay

Prove the identity:
$\cos 3 x=\cos ^{3} x-3 \sin ^{2} x \cos x$

Understand the fundamental properties of probability distributions, including the rule that the sum of all probabilities equals 1.

Grasp the concept of independence between two variables and how it's determined using probability distributions.

Compute expected values (E) for specific random variables given their probability distributions.

Understand and calculate the variance (V) and standard deviation of random variables and how they reflect the data's spread.

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