matematika



Please Solve this tricky Trignometric equation

Trigonometry equalities, inequalities and expressions - sin, cos, tan, cot

Please Solve this tricky Trignometric equation

Postby parmar.abhishek » Sun Sep 19, 2010 5:40 am

I have tried in many ways to solve this equation.
Please help me on the solution. This problem is from R.D Sharma

Sin x + tan x = √3


parmar.abhishek
 
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Postby Math Tutor » Sun Sep 19, 2010 9:33 am

Maybe there are many ways to solve this trigonometric equation:

I use the following trigonometric formulas:

sin2u = \frac{2tan^2u}{1+tan^2u}
and
tan2u = \frac{2tan^2u}{1 - tan^2u}

so:

\frac{2tan^2\frac{x}{2} }{1+tan^2\frac{x}{2}} + \frac{2tan^2\frac{x}{2} }{1-tan^2\frac{x}{2}} = \sqrt{3}

\frac{4tan^2\frac{x}{2} }{1-tan^4\frac{x}{2}}  = \sqrt{3}


now replace tan^2\frac{x}{2} = t
and solve the quadratic equation.
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wrong formula used

Postby parmar.abhishek » Mon Sep 20, 2010 12:54 pm

the formula used for tan 2u is not correct.

Please check that again.
I am tired of this solution please someone help me with this problem.
parmar.abhishek
 
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Please anyone reply

Postby parmar.abhishek » Wed Sep 22, 2010 1:27 pm

When I saw the solution, I was thinking myself as a fool not able to do such easy steps and was happy to see the solution.
But when I discovered that the formula used is wrong, I am again stuck with this problem.
And I am waiting for someone who can help me in any way.
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Postby Math Tutor » Fri Sep 24, 2010 6:00 am

The both formulas are wrong. it is 2tan not 2tan2
I will think once again.
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Postby Math Tutor » Wed Sep 29, 2010 1:29 am

Here is the discussion in the bulgarian math forum:
http://www.math10.com/f/viewtopic.php?f=49&t=3198

You could use google translate.
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