Answers

2015-08-10T23:13:04+05:30
Sec 4A = cosec (A-20°)
cosec(90-4A)=cosec(A-20°)
comparing both sides,
90-4A=A-20
-4A-A=-20-90
-5A=-110
5A=110
A=110÷5
A=22
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