Correct Answer is : None of the above

NIMCET 2015 Question Paper with solutions

Question : 2 of 120

Marks: +1, -0

If 0 < x < π and cos x + sin x =

1/2

, then the value of tan x is :

Solution:

We have, 0 < x < n and

\cos x+\sin x=1/2

⇒(\cos x+\sin x)^{2}={1}/{4}

⇒1+\sin 2x={1}/{4}

⇒\sin 2x=\;\;{-3}/{4}

⇒{2\tan x}/{1+\tan^{2}x}=\;\;{-3}/{4}

⇒3\tan^{2}x+8\tan x+3=0

\tan x={-8±√{64-36}}/{6}

\tan x={-8±2√{7}}/{6}={-4±√{7}}/{3}

\tan x={-(4+√{7})}/{3}

{-4+√{7}}/{3}

Go to Question:

Prev Question

Next Question