Math

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Show that

sinx = (square root of) 1 - cos^2x

is not an identity

  • Math -

    All we need is one counterexample to show it is not an identity.

    let x = 210º
    LS = sin 210 = -1/2
    RS = √(1- cos^2 (210º))
    = √(.25)
    = 1/2

    So there!

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