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Help!
solve for:
sin (pi/4 -x) - sin (x + pi/4) for 0 < x < 2pi

Help! solve for: sin (pi/4 -x) - sin (x + pi/4) for 0 < x < 2pi-example-1
User Aryeh Beitz
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1 Answer

30 votes
30 votes

Answer:

sin(pi/4 - x) - sin(x + pi/4) = 1


( √(2) )/(2) ( \cos(x) - \sin(x) ) - ( √(2) )/(2) ( \sin(x) + \cos(x) ) = 1 \\ \\ < = > - 2 * ( √(2) )/(2) \sin(x) = 1 \\ \\ < = > \sin(x) = ( - 1)/( √(2) ) \\ \\ < = > x = - (\pi)/(4) + k2\pi \: or \: x = (5\pi)/(4) + k2\pi

but 0 < x< 2pi => x = { 5pi/4; 7pi/4 }

User Mtk
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