Trigonometry

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12. Find the exact value of sin(2x) if sin(x)=-1/2.

sin(2x) = 2sin(x)cos(x)

  • Trigonometry -

    if sinx=-1/2, then cosx=sqrt(1-1/4)=sqrt(3/4)=sqrt3 /2

    sin(2x)=2*(-1/2)(sqrt3 /2)
    = -1/2 sqrt3

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