Question 397299
pi is less than or equal to (theta) is less than or equal to 3pi over 2. 
sin(theta)=-0.9419 
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Theta is in the 3rd Quadrant.
sin^-1(-0.9419) = -1.2282 = (2(pi))-1.2282 = 5.0549
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Cheers,
Stan H.