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FP1 Maths Question..need help please Watch

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    I've got the equation that k=-x but I don't feel that it's right
    My results are k=0,1
    Could someone tell me whether they are right or not? Thanks
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    You are correct, you should be able to verify this yourself.
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    (Original post by Oliviazh)
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    I've got the equation that k=-x but I don't feel that it's right
    My results are k=0,1
    Could someone tell me whether they are right or not? Thanks
    Well, multiply the first equation by 3 and the second by 2 and then subtract to get (6x^2 + 9x + 3k) - (6x^2 + 2x - 4k) = 7x + 7k = 0 \iff x = -k as you've suggested.

    So you need to solve 3k^2 - k - 2k = 3(k^2-k) = 0 \iff k = 0 \, \mathrm{or}\, k = 1 as you suggested. So you are indeed correct.
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    (Original post by Zacken)
    Well, multiply the first equation by 3 and the second by 2 and then subtract to get (6x^2 + 9x + 3k) - (6x^2 + 2x - 4k) = 7x + 7k = 0 \iff x = -k as you've suggested.

    So you need to solve 3k^2 - k - 2k = 3(k^2-k) = 0 \iff k = 0 \, \mathrm{or}\, k = 1 as you suggested. So you are indeed correct.
    Thank you V much!
 
 
 
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