Problem in finding the General Solution of a Trigonometric Equation v3

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Homework Statement

:[/B]

Find the general solution of the Trigonometric equation: $$3\sin ^2 {\theta} + 7\cos ^2 {\theta} =6$$

Given andwer: ##n\pi \pm \frac {\pi}{6}##

Homework Equations

:[/B]

These equations may help:

20170519_023122.png


The Attempt at a Solution

:[/B]

Please see the pic below:

14951886349821598693691.jpg


It seems correct from my side, but the answer is not matching.
 
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Is there really a difference :smile: ?
 
Fill in n = 1, 2, 3 in both expressions (yours and the book one) :rolleyes:
 
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There is a pi radian difference between -pi/6 and 5pi/6, same with pi/6 and -5pi/6. So you can just say it is +-pi/6 + n*pi, where n can be any integer. That covers all of your scenarios.
 
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scottdave said:
There is a pi radian difference between -pi/6 and 5pi/6, same with pi/6 and -5pi/6. So you can just say it is +-pi/6 + n*pi, where n can be any integer. That covers all of your scenarios.
Why don't you let Wrichik make that discovery himself ?
 
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scottdave said:
There is a pi radian difference between -pi/6 and 5pi/6, same with pi/6 and -5pi/6. So you can just say it is +-pi/6 + n*pi, where n can be any integer. That covers all of your scenarios.

BvU said:
Why don't you let Wrichik make that discovery himself ?
understood. Thank you.
 
BvU said:
Why don't you let Wrichik make that discovery himself ?
Thanks. I guess I didn't see your response about plugging in 1,2,3, etc when I wrote my suggestion.