document.write( "Question 526662: please help me urgently....
\n" ); document.write( "1)Find m and n if (x-2) and (x+3) are both factors of x^3+mx^2-nx-6
\n" ); document.write( "2) When p(x)=x^4-3x^3+ax^2+bx-6 is divided by (x+1)it has a remainder of 8. If (x-3) is a factor of p(x) find a and b.
\n" ); document.write( "3) If x^2-4 is a factor of 2x^3-ax^2+bx+4 find a and b. \r
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Algebra.Com's Answer #348647 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
When you divide a polynomial P(x) by a divisor polynomial D(x) you get a quotient polynomial Q(x) and a remainder polynomial R(x). With some luck, all of those polynomial will be very small and simple, and maybe the remainder will be 0, or just a number (a polynomial of degree zero).\r
\n" ); document.write( "\n" ); document.write( "1) \"P%28x%29=x%5E3%2Bmx%5E2-nx-6=%28x-2%29Q%28x%29\" (remainder is zero) means that
\n" ); document.write( "\"P%282%29=2%5E3%2Bm%282%5E2%29-2n-6=%282-2%29Q%282%29=0\"
\n" ); document.write( "\"8%2B4m-2n-6=0\" or \"4m-2n=-2\"
\n" ); document.write( "Similarly
\n" ); document.write( "\"P%28-3%29=0\" leads you to \"9m%2B3n=33\"
\n" ); document.write( "Those two equations form a linear system that allows you to find m and n.\r
\n" ); document.write( "\n" ); document.write( "2) Same idea
\n" ); document.write( "\"P%28x%29=%28x-3%29Q%28x%29\" (remainder is zero) so \"P%283%29=0\" and
\n" ); document.write( "\"P%28x%29=%28x%2B1%29Q%28x%29%2B8\" (remainder is 8) so \"P%28-1%29=8\"
\n" ); document.write( "You'll get two equations that would allow you to find a and b.\r
\n" ); document.write( "\n" ); document.write( "3) \"P%28x%29=%28x%5E2-4%29Q%28x%29=%28x-2%29%28x%2B2%29Q%28x%29\" (remainder is zero)
\n" ); document.write( "I would bet on
\n" ); document.write( "\"Q%28x%29=2x-1\" and \"P%28x%29=%28x%5E2-4%29%282x-1%29\"
\n" ); document.write( "Multiplying will tell you if that product is a polynomial that could be the one you were given. (Easy way to solve it).
\n" ); document.write( "You are probably expected to use
\n" ); document.write( "\"P%282%29=0\" and \"P%28-2%29=0\"
\n" ); document.write( "to set up a system of equations to solve for a and b, but who really enjoys solving systems of equations?
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