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by **mrwisdom** on Fri Apr 22, 2011 9:47 pm

when 10x^3 +mx^2 -x +10 is divided by 5x-3, the quotient is 2x^2 +nx - 2 and the remainder is 4. find the values of m and n

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by **nona.m.nona** on Fri Apr 22, 2011 11:43 pm

mrwisdom wrote:when 10x^3 +mx^2 -x +10 is divided by 5x-3, the quotient is 2x^2 +nx - 2 and the remainder is 4. find the values of m and n

What expressions did you get for the quotient and the remainder when you did the long division? When you set your expressions equal to the given expression and value, where did this lead?

Thank you.

by **mrwisdom** on Sun Apr 24, 2011 7:56 pm

im not sure i understand what you mean.

by **Martingale** on Sun Apr 24, 2011 11:50 pm

mrwisdom wrote:when 10x^3 +mx^2 -x +10 is divided by 5x-3, the quotient is 2x^2 +nx - 2 and the remainder is 4. find the values of m and n

$\frac{10x^3+mx^2-x+10}{5x-3}=2x^2+nx-2+\frac{4}{5x-3}$

$2x^2+nx-2+\frac{4}{5x-3}=\frac{(2x^2+nx-2)(5x-3)}{5x-3}+\frac{4}{5x-3}=\frac{(2x^2+nx-2)(5x-3)+4}{5x-3}$

thus

$10x^3+mx^2-x+10=(2x^2+nx-2)(5x-3)+4$

expand and solve for $n$ . Then you will be able to get $m$

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