If tan 2A=cot(A-18°), where 2A is an acute angle, find the value of A

1.	If tan 2A=cot(A-18°), where 2A is an acute angle, find the value of A.
Answer» Given\xa0tan2A=cot(A−180)⇒cot(90−2A)=cot(A−180)[∵tanθ=cot(90−θ)]Comparing angles we get90−2A=A−18⇒90+18=A+2A⇒3A=108⇒A=108\u200b/3⇒A=36∘

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