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Question

Find all solutions to  on the interval 

 =  

 Give your answers as exact values, as a list separated by commas

Answer 1

sin(theta) =-sqr2/2

that's a reference angle of 45 degrees = pi/4

the negative sign though puts the angle in quadrant III or IV

so theta = 180+45 = 225 or 360-45 = 315

225 degrees = 5pi/4 radians

315 degrees = 7pi/4 radians

5pi/4, 7pi/4