Q19 of 30 Page 1

If 4 tanθ = 3, evaluate

OR


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

Given:

We can picture this using the right triangle below:



Now, Using the Pythagoras Theorem i.e.


AC = 5k




Putting the values in the expression given



OR


Given:


• tan 2A = cot (A – 18°)


• 2A is Acute


We know,



Putting θ = 2A



Now, 2A is acute


(A – 18°) and (90° – 2A) is acute


⇒ 90° – 2A = A – 18°


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