Question

If tan 2A = cot (A -18°), where 2A is an acute angle, find the value of A.
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Answer 1

Answer:tan(2A)=cot(A-18)

Cot(90-A)=cot(A-18)

As functions are same than angles are same

108=2A

A=54

Step-by-step explanation:

Answer 2

 Solution:

It is given that tan2A=cot(A−18°)

 ⇒tan2A=cot(90° −(108° −A))

⇒tan2A=tan(108° −A)        

{°•° cot(90° −A)=tan(A)}

 ⇒2A=108° −A

 ⇒3A=108°

 ⇒A=108°/3 =36°

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