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Question
Evaluate:
`2 tan57^circ/(cot33^circ) - cot70^circ/(tan20^circ) - sqrt(2) cos45^circ`
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Solution
`2 tan57^circ/(cot33^circ) - cot70^circ/(tan20^circ) - sqrt(2) cos45^circ`
`2 tan(90^circ - 33^circ)/(cot33^circ) - cot(90^circ - 20^circ)/(tan20^circ) - sqrt(2)(1/sqrt2)`
`2 cot33^circ/(cot33^circ) - tan20^circ/(tan20^circ) - 1`
= 2 – 1 – 1
= 0
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