You can put this solution on YOUR website! Find the exact value of sin θ, if cos θ = 4/5 and θ lies in quadrant IV.
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Plot the terminal point on the x-y grid
x = 4, r = 5
y = 3 (by Pythagoras) --> -3 in Q4
sin = y/r
sin = -3/5
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Or do it this way:
sin^2 + cos^2 = 1
sin = sqrt(1 - cos^2) = 3/5 or -3/5
Q4 --> -3/5
