Evaluating the composition of Functions using Right Triangles

The video tutorial explains how to evaluate the cosine of the arcsine of 2X. It begins by introducing the problem and the need to construct a triangle to find the angle whose sine is 2X. The tutorial discusses the selection of the correct triangle based on the range of the inverse sine function. It then derives the formula for the adjacent side of the triangle and uses it to determine the cosine. The final solution is presented as the cosine of the angle, calculated as the adjacent side over the hypotenuse.

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