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Lv 4
? asked in Science & MathematicsMathematics · 5 years ago

How can I write cos(2t) like a function of sin(t) ?

The answer must contain a polynom or a rational function f(x) ,taking into consideration that cos(2t)=f(sin(t))

4 Answers

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  • Elizabeth M
    Lv 7
    5 years ago
    Favorite Answer

    cos(2t)=1-2sin^2(t)=f(sin(t)).

    f(x)=1-2x^2

  • Como
    Lv 7
    5 years ago

    cos (2t) = cos²t - sin²t

    cos (2t) = 1 - 2 sin²t

  • ?
    Lv 7
    5 years ago

    double angle identity

    cos(2t)=cos^2(t)-sin^2(t)

    Pythagorean identity

    1 = sin^2(t)+cos^2(t)

    1-cos(2t) = 2sin^2(t)

    cos(2t) = 1 - 2sin^2(t)

  • DWRead
    Lv 7
    5 years ago

    double-angle formula:

    cos(2t) = 1 - 2sin²(t)

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