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Math Help - trig equation

  1. #1
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    trig equation

    I have no idea how to solve an equation
    -1.2sin2t+0.8cost=0.8
    (tried all trig formulas and substitution method)
    If anybody could help?
    Thanks.
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  2. #2
    MHF Contributor
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    Quote Originally Posted by Romanka View Post
    I have no idea how to solve an equation
    -1.2sin2t+0.8cost=0.8
    (tried all trig formulas and substitution method)
    Is the first term -1.2 sin(2t) or -1.2 sin^2(t)?

    Thank you!
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  3. #3
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    -1.2sin(2t)+0.8cost=0.8
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  4. #4
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    Quote Originally Posted by Romanka View Post
    -1.2sin(2t)+0.8cost=0.8
    sin(2t) = 2sin(t)cos(t)

    Multiply that by -1.2 and factor out cos(t). Then solve using both cos and sin
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  5. #5
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    I tried all these steps, but there is 0.8 in the right side.
    I have
    3sintcost-cost+1=0 and can't solve it
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