-2sinx+2cos2x=0
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-2sinx+2cos2x= -2sinx + 2(1 - 2sin^2x)
= -2 sinx + 2 - 4sin^2x
= -4sin^2x -2 sinx + 2
= -4sin^2x -4sinx +2sinx +2
= -4sinx (sinx + 1) +2 ( sinx + 1 )
= (-4 sinx + 2 ) ( sinx + 1) = 0 ,
-4sinx + 2 = 0
-4sinx = -2
sinx = 1/2
so, x = 30* or x = 270* degree
= -2 sinx + 2 - 4sin^2x
= -4sin^2x -2 sinx + 2
= -4sin^2x -4sinx +2sinx +2
= -4sinx (sinx + 1) +2 ( sinx + 1 )
= (-4 sinx + 2 ) ( sinx + 1) = 0 ,
-4sinx + 2 = 0
-4sinx = -2
sinx = 1/2
so, x = 30* or x = 270* degree
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