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    Could someone help with example 12 on page 9. I am unsure, what they mean by "comparing the coefficients in x3" and "comparing the coefficients in x2"

    Link: http://www.scribd.com/doc/131321174/...aths-C3#scribd

    Thanks!!
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    The coefficient of x^3 is just the constant by which x^3 is multiplied; likewise for x^2. Since x can vary, for both sides of this equation to be identical regardless of the value of x, we need the coefficients for the different powers of x to be the same on each side.
    So what you are doing is comparing the left hand side to the right hand side, as you know they are identical. The coefficient of x^3 is clearly 1. If you multiply out the right hand side, you will find that the only x^3 term is Ax^3. Hence A = 1.
    You also know that the coefficient of x^2 is 1. If you multiply out the right hand side, you can similarly find B.
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    (Original post by 13 1 20 8 42)
    The coefficient of x^3 is just the constant by which x^3 is multiplied; likewise for x^2. Since x can vary, for both sides of this equation to be identical regardless of the value of x, we need the coefficients for the different powers of x to be the same on each side.
    So what you are doing is comparing the left hand side to the right hand side, as you know they are identical. The coefficient of x^3 is clearly 1. If you multiply out the right hand side, you will find that the only x^3 term is Ax^3. Hence A = 1.
    You also know that the coefficient of x^2 is 1. If you multiply out the right hand side, you can similarly find B.
    Thank you so much!!
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    (Original post by JamesNeedHelp2)
    Could someone help with example 12 on page 9. I am unsure, what they mean by "comparing the coefficients in x3" and "comparing the coefficients in x2"

    Link: http://www.scribd.com/doc/131321174/...aths-C3#scribd

    Thanks!!
    Hows C3 and C4 ?I also do Maths and how difficult was the AS maths exams in the summer ?
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    (Original post by Kadak)
    Hows C3 and C4 ?I also do Maths and how difficult was the AS maths exams in the summer ?
    I guess its subjective, harder for some, easier for others. ^^
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    (Original post by JamesNeedHelp2)
    ^^
    If 2 polynomials are identical then each element has the same coefficient

    ax^3+bx^2+cx+d \equiv ex^3+fx^2+gx+h

    Means a=e and b=f etc

    If you have a problem to look at ... Please post it
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    (Original post by TenOfThem)
    If 2 polynomials are identical then each element has the same coefficient

    ax^3+bx^2+cx+d \equiv ex^3+fx^2+gx+h

    Means a=e and b=f etc

    If you have a problem to look at ... Please post it
    Thank you so much. I will do, if i get stuck.
 
 
 
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