Question 1078890
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sin10°cot 20°cos 30°tan40°tan50°cosec 60°cot70°sec 80°=1 prove.
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Use basic trigonometry identities:


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1.  sin(10°) = cos(80°) = {{{1/sec(80^o)}}}   --->  sin(10°)*sec(80°) = 1.


2.  cot(20°) = {{{1/cot(70^o)}}}   --->  cot(20°)*cot(70°) = 1.


3.  cos(30°) = sin(60°) = {{{1/cosec(60^o)}}}   --->  cos(30°)*cosec(60°) = 1.


4.  tan(40°) = {{{1/tan(50^o)}}}   --->  tan(40°)*tan(50°) = 1.



5.  =======>  sin10°cot 20°cos 30°tan40°tan50°cosec 60°cot70°sec 80° = 1.   Proved.
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