tan⁡2(sec⁡−12)+cot⁡2(csc⁡−13).\tan^2(\sec^{-1} 2) + \cot^2(\csc^{-1} 3).

Problem

tan⁡2(sec⁡−12)+cot⁡2(csc⁡−13).\tan^2(\sec^{-1} 2) + \cot^2(\csc^{-1} 3).
Intuitive explanation

This problem asks you to evaluate expressions involving inverse trig functions—the key is to construct a right triangle for each inverse function, then read off the sides you need. For sec⁡−12\sec^{-1} 2, ask "what angle has secant equal to 2?" and sketch a triangle where the hypotenuse is 2 and the adjacent side is 1. Similarly, for csc⁡−13\csc^{-1} 3, build a triangle with hypotenuse 3 and opposite side 1. Once you have the triangles, use the Pythagorean theorem to find the missing sides, then compute tan⁡2\tan^2 and cot⁡2\cot^2 directly from those side lengths.

Intuitive explanation

This problem asks you to evaluate expressions involving inverse trig functions—the key is to construct a right triangle for each inverse function, then read off the sides you need. For sec⁡−12\sec^{-1} 2, ask "what angle has secant equal to 2?" and sketch a triangle where the hypotenuse is 2 and the adjacent side is 1. Similarly, for csc⁡−13\csc^{-1} 3, build a triangle with hypotenuse 3 and opposite side 1. Once you have the triangles, use the Pythagorean theorem to find the missing sides, then compute tan⁡2\tan^2 and cot⁡2\cot^2 directly from those side lengths.

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