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if sin theta equals 3/5 and theta is second quadrant angle find tan 2 theta.my ans. was 3.442 but is wrong can you correct and show work please. thank you so much.

  • math -

    3,4,5 right triangle in quadrant 2
    cos t = -4/5
    tan t = sin t/cos t = -3/4
    tan 2 t = 2 tan t / (1-tan^2 t)
    = 2 (-3/4) / (1-9/16)
    = (-3/2)/(7/16)
    = -3 /(7/8)
    = -24/7
    =-3.43

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