How to use right triangles to evaluate the composition of a trig function and its inverse

The video tutorial explains the concept of cosine inverse, representing it as an angle, and how it relates to cosine. The instructor demonstrates how to use this understanding to draw a right triangle and calculate the tangent of the angle using the Pythagorean theorem. The process involves identifying the missing side of the triangle and using it to find the tangent, emphasizing the lack of restrictions in this context.

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