Simplify trigonometric expression

courteous

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Simplify: \(\displaystyle \frac{2\sin{x}+1}{\sqrt3 - 2\cos{x}}\)

What I've come to thus far (by multiplying with \(\displaystyle \frac{\sqrt3 + 2\cos{x}}{\sqrt3 + 2\cos{x}}\) and \(\displaystyle \frac{2\sin{x}-1}{2\sin{x}-1}\)) is \(\displaystyle \frac{\sqrt3 + 2\cos{x}}{2\sin{x}-1}\) :x

Oh, not to forget, the solution deals with \(\displaystyle \cot\) (cotangens).
 
courteous said:
Simplify: \(\displaystyle \frac{2\sin{x}+1}{\sqrt3 - 2\cos{x}}\)

What I've come to thus far (by multiplying with \(\displaystyle \frac{\sqrt3 + 2\cos{x}}{\sqrt3 + 2\cos{x}}\) and \(\displaystyle \frac{2\sin{x}-1}{2\sin{x}-1}\)) is \(\displaystyle \frac{\sqrt3 + 2\cos{x}}{2\sin{x}-1}\) :x

Oh, not to forget, the solution deals with \(\displaystyle \cot\) (cotangens).

Please share with us the "exact" form you are given as answer.

Without knowing the form that is wanted - I would do it the following way

\(\displaystyle \frac{2sin(x) + 1}{\sqrt{3}-2cos(x)}\)

\(\displaystyle = \, \frac{sin(x) + \frac{1}{2}}{\frac{\sqrt{3}}{2}-cos(x)}\)

\(\displaystyle = \, \frac{sin(x) + \, sin(\frac{\pi}{6})}{cos(\frac{\pi}{6}) \, - \, cos(x)}\)

then use the fact that:

\(\displaystyle sin(A) \, + \, sin(B) \, = \, 2\cdot sin(\frac{A+B}{2})\cdot cos(\frac{A-B}{2})\)

and similar form for cosines.

That should take you to the "allegedly simlified" cotangent form.
 
With sum as product, I managed to take it to given solution \(\displaystyle \cot\frac{x-\frac{\pi}{6}}{2}\).
 
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