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    Solve the equation 2sin^2theta = costheta + 2 for values between 0 and 360 degrees.

    So the identities are:

    sin^2theta + cos^2theta

    tantheta=sintheta/costheta


    Any help as to how this can be solved would be very much appreciated, thanks
    And sorry for the lack of the use of latex!
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    You are having problems as part of your first identity is missing. This is the one you want to use.
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    (Original post by x-Sophie-x)
    Solve the equation 2sin^2theta = costheta + 2 for values between 0 and 360 degrees.

    So the identities are:

    sin^2theta + cos^2theta

    tantheta=sintheta/costheta


    Any help as to how this can be solved would be very much appreciated, thanks
    And sorry for the lack of the use of latex!
    You want a quadratic in cos

    \sin^2 \theta + \cos^2 \theta = 1
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    You're both analogous to Speedy Gonzales
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    (Original post by Indeterminate)
    You want a quadratic in cos

    \sin^2 \theta + \cos^2 \theta = 1
    What do you mean by that?

    So far I've got:

    2(1-cos^2theta)=costheta +2
    2-2cos^2theta=costheta +2
    -2cos^2theta=costheta

    Where do I go after that?
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    (Original post by Felix Felicis)
    You're both analogous to Speedy Gonzales
    I'm sorry, but what?
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    (Original post by x-Sophie-x)
    What do you mean by that?

    So far I've got:

    2(1-cos^2theta)=costheta +2
    2-2cos^2theta=costheta +2
    -2cos^2theta=costheta

    Where do I go after that?
    Get everything on one side and factorise
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    (Original post by x-Sophie-x)
    I'm sorry, but what?
    Nevermind, I was referring to Indeterminate and Mr M xD In response to your last question, you have a quadratic in costheta, solve how you normally would
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    (Original post by x-Sophie-x)
    I'm sorry, but what?
    He means that we were too quick (comparison to speedy gonzales)
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    (Original post by Felix Felicis)
    Nevermind, I was referring to Indeterminate and Mr M xD In response to your last question, you have a quadratic in costheta, solve how you normally would
    Oh I see.

    And I have no idea what you mean by that.

    costheta +2cos^2theta=0
    costheta(1+2costheta)=0

    But how would that help me in any way?
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    (Original post by Indeterminate)
    He means that we were too quick (comparison to speedy gonzales)
    Ah right.
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    (Original post by x-Sophie-x)
    Oh I see.

    And I have no idea what you mean by that.

    costheta +2cos^2theta=0
    costheta(1+2costheta)=0

    But how would that help me in any way?
    ab = 0 means a = 0 or b = 0

    Arriba! Arriba!
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    (Original post by x-Sophie-x)
    Oh I see.

    And I have no idea what you mean by that.

    costheta +2cos^2theta=0
    costheta(1+2costheta)=0

    But how would that help me in any way?
    You have \cos \theta (1 + 2 \cos \theta ) = 0 \Rightarrow \cos \theta = 0 or \cos \theta = -\frac{1}{2}
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    ^^beat me to it
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    (Original post by Mr M)
    ab = 0 means a = 0 or b = 0

    Arriba! Arriba!
    And again! xD
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    (Original post by Felix Felicis)
    And again! xD
    I see what you meant by MrM now, I hadn't a clue who he was.
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    (Original post by x-Sophie-x)
    I see what you meant by MrM now, I hadn't a clue who he was.
    My fame precedes me.

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    (Original post by Felix Felicis)
    You have \cos \theta (1 + 2 \cos \theta ) = 0 \Rightarrow \cos \theta = 0 or \cos \theta = -\frac{1}{2}
    Oh yeah. Funny how I didn't see that, thanks

    It's annoying how you know the answer to every maths question though :P
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    (Original post by Mr M)
    My fame precedes me.

    Haha. Sorry
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    (Original post by x-Sophie-x)
    Oh yeah. Funny how I didn't see that, thanks

    It's annoying how you know the answer to every maths question though :P
    :smug: Jelly?

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    Ha, I'm still merely an infant in the field of mathematics and have barely scratched the surface
 
 
 
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