VERIFY an expression by using the difference of two angles of sine

The video tutorial explains how to simplify the expression sine(π/2 - X) using the difference formula for sine functions. Initially, the cofunction identity is mentioned, but the focus is on proving the expression equals cosine(X) through the sum and difference formulas. The tutorial provides a detailed step-by-step process, labeling the angles and applying the formula, leading to the evaluation and confirmation of the result.

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