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Help with this math question!

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    The equation:

    y = 3x^2 + (k-2)x + 3

    Has two real roots.

    Work out the values of k.

    I'd be grateful if anyone could help me with this
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    (Original post by Federerr)
    The equation:

    y = 3x^2 + (k-2)x + 3

    Has two real roots.

    Work out the values of k.

    I'd be grateful if anyone could help me with this
    Use b^2 -4ac
    where
    a=3
    b=k-2
    c=3

    the question tells us the equation has 2 real roots
    \therefore b^2 -4ac > 0
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    (Original post by Federerr)
    The equation:

    y = 3x^2 + (k-2)x + 3

    Has two real roots.

    Work out the values of k.

    I'd be grateful if anyone could help me with this
    use the discriminant and 2 real roots means that the equation must be greater than 0 solve from there
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    (Original post by hamza772000)
    use the discriminant and 2 real roots means that the equation must be greater than 0 solve from there
    Well I know that haha.

    I got an answer just wanna see if I got it right

    Do it hamza lemme know what yah get init.
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    (Original post by Federerr)
    Well I know that haha.

    I got an answer just wanna see if I got it right

    Do it hamza lemme know what yah get init.
    lemme have a go then
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    (Original post by Federerr)
    Well I know that haha.

    I got an answer just wanna see if I got it right

    Do it hamza lemme know what yah get init.
    I got K=8 and K=-4
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    (Original post by Federerr)
    Well I know that haha.

    I got an answer just wanna see if I got it right

    Do it hamza lemme know what yah get init.
    k>8
    k<-4
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    (Original post by will'o'wisp)
    k>8
    k<-4
    That's what I got
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    (Original post by hamza772000)
    I got K=8 and K=-4
    but it's an inequality you're solving.... you even said set the discriminant greater than 0...
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    (Original post by Federerr)
    That's what I got
    Awesome i sometimes do dis and ask ppl to do the question for me and check if i got the right answer xD
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    (Original post by Federerr)
    Well I know that haha.

    I got an answer just wanna see if I got it right

    Do it hamza lemme know what yah get init.


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    (Original post by will'o'wisp)
    Awesome i sometimes do dis and ask ppl to do the question for me and check if i got the right answer xD
    Yehh! It's so frustrating when you can't find the solutions anywhere haha.
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    (Original post by will'o'wisp)
    but it's an inequality you're solving.... you even said set the discriminant greater than 0...
    Yeah, I realised, look at the attachment below
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    Nice handwriting
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    That's calm.

    > 8
    < -4
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    (Original post by Federerr)
    Nice handwriting
    It was in a rush, r u taking the piss? lol :P
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    (Original post by hamza772000)
    It was in a rush, r u taking the piss? lol :P
    Nah it's actually naaaaas
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    (Original post by Federerr)
    Nah it's actually naaaaas
    well, here it's nasty but ok :P
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    (Original post by hamza772000)
    well, here it's nasty but ok :P
    I got handwriting like a yr 2 kid
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    (Original post by Tasnia'x)
    That's calm.

    > 8
    < -4
    woah sorry.

    we ain't all as clever as u.

    Spoiler:
    Show
    :smug:

    about dats calm
 
 
 
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