Choose the correct option and justify your choice :

 \(\dfrac{ 2\;tan \;30°}{1+tan^230°} \) =

(A) sin 60°            

(B) cos 60°          

(C) tan 60°            

(D) sin 30°

Asked by Pragya Singh | 1 year ago |  122

1 Answer

Solution :-

Right answer is  (A)  sin 60° 

Substitute the of tan 30° in the given equation

tan 30° = \( \dfrac{1}{\sqrt{3}}\)

2\( (\dfrac{1}{\sqrt{3}})=1+(\dfrac{1}{\sqrt{3}})2\)

\( \dfrac{2}{\sqrt{3}}=1+\dfrac{1}{3}\)

\(\dfrac{6\sqrt{3}}{4}=\dfrac{\sqrt{3}}{2} \) = sin 60°

The obtained solution is equivalent to the trigonometric ratio sin 60°

Answered by Abhisek | 1 year ago

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Class 10 Maths Introduction to Trigonometry View Answer