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    step by step please
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    (Original post by piamiahh)
    step by step please
    What have you tried so far?
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    step by step please
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    (Original post by piamiahh)
    step by step please
    sin2x = 2sinxcosx

    You should be able to solve it from there.
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    (Original post by Notnek)
    What have you tried so far?
    2(2sinxcosx)-3sinx = 0

    but don't really know what can happen now
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    (Original post by piamiahh)
    2(2sinxcosx)-3sinx = 0

    but don't really know what can happen now
    So you have

    4sin(x)cos(x)-3sin(x) = 0

    Notice that sin(x) is a common factor so you can factorise. Try this and post your working if you get stuck.
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    2sin2x = 3sinx
    2(2sinxcosx) - 3sinx = 0

    - Started it off for you
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    sin2x=2sinxcosx

    This should hopefully be enough.

    If you forget this you have the formula sheet which says sin(A+B)=SinACosB+SinBCosA. If you input x as A and B you get sinxcos + sinxcosx which is 2sinxcosx
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    >inb4 divides through by sin(x)
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    (Original post by piamiahh)
    2(2sinxcosx)-3sinx = 0

    but don't really know what can happen now
    what are the common terms between those terms, 2(2sinxcosx) = 3sinx
    if you identify it, you can divide both sides from it.
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    4sinxcosx-3sinx=o.
    Sinx(4cosx-3)=0
    Sinx=o. Cosx=3/4
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    (Original post by RDKGames)
    >inb4 divides through by sin(x)
    (Original post by YouMadBro!)
    what are the common terms between those terms, 2(2sinxcosx) = 3sinx
    if you identify it, you can divide both sides from it.
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    sinx can be taken out as a factor :-)
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    (Original post by RDKGames)
    >inb4 divides through by sin(x)
    You lose the sinx solutions if you do that, you’ll only get the ones for cosx unless you meant factor out
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    (Original post by Notnek)
    So you have

    4sin(x)cos(x)-3sin(x) = 0

    Notice that sin(x) is a common factor so you can factorise. Try this and post your working if you get stuck.
    got it! thank you!!
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    (Original post by Notnek)
    Bound to happen on EVERY.SINGLE.THREAD :lol:
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    (Original post by Zxyn)
    You lose the sinx solutions if you do that, you’ll only get the ones for cosx unless you meant factor out
    It was a joke.
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    I got sinx = 0 and 4cosx=3
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    cosx = 3 divided by 4

    is this correct...

    i'm in gcse
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    Name:  4C9D188D-705B-4A4F-805E-FE5452E24B0F.jpg.jpeg
Views: 75
Size:  15.6 KB hope this helps
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