Question

if tan 2A =case (A-18°) where 2A is an acute angle find value of A

Answer 1

cot(90-2A)=cot(A-18)
90+18=A+2A
108=3A
A=36°

Answer 2

Answer:

36°

Step-by-step explanation:

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°

Thanks ☺