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Question : 106 of 200
Marks:
+1,
-0
Solution:
(4) (tan1°cot2°tan3°cot4°……cot 86°tan 87°cot 88°tan 89°)
= (tan1°cot2°tan3°cot4°…cot44°tan45°cot46°… cot86°tan87°cot88°tan89°)
= tan1°cot2°… cot44°tan45°cot(90°- 44°) … cot (90°– 4°) tan(90°– 3°) cot (90°– 2°) tan (90°–1°)
= tan1° cot2°…cot44°tan45°tan44°… tan4°cot3°tan2°cot1°
= tan 45°= 1
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