Question 944480
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Solve for all 0 degrees less than or equal to x less than 360 degrees.
(a) 3tan x- sqrt( 3 )=0
(b) 2sin x cos x=2sin x
(c) cos^2 x-sin^2 x + 3cos x - 1=0
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In the post by @lwsshar3, the solution to (a) is incorrect: 150˚ is WRONG answer.

The solution to (b) is incorrect, too: some roots are missed.

I came to bring correct solutions to (a) and (b).



- - - (a) - - - 


3tan x- sqrt( 3 )= 0
tanx = √3/3
x = 30˚ or 210˚.


<U>ANSWER to (a)</U>.  x = 30˚ or 210˚.



- - - (b) - - - 


2sin(x)*cos(x) = 2sin(x)
2sin(x)*cos(x) - 2sin(x) = 0
2sin(x)*(cos(x)-1)) = 0


case 1. sin(x) = 0 ---> x = 0˚ or x = 180˚.


case 2. cos(x) = 1 ---> x = 0˚.



<U>ANSWER to (b)</U>.  x = 0˚ or x = 180˚.