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Question
Evaluate: `2(tan57°)/(cot33°) - (cot70°)/(tan20°) - sqrt(2) cos 45°`
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Solution
`2(tan57°)/(cot33°) - (cot70°)/(tan20°) - sqrt(2) cos 45°`
= `2(tan(90° - 33°))/(cot33°) - (cot(90° - 20°))/(tan20°) - sqrt(2) (1/sqrt(2))`
= `2(cot33°)/(cot33°) - (tan20°)/(tan20°) - 1`
= 2 - 1 - 1
= 0.
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