document.write( "Question 117478: decompose into a partial fraction\r
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document.write( "2x^3+x^2-3x+5 / x^2-2x-3 \n" );
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Algebra.Com's Answer #85998 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Decompose into a partial fraction \n" ); document.write( ": \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Numerator degree is greater than the denominator: \n" ); document.write( "Divide using long division: \n" ); document.write( "......................___________________ \n" ); document.write( "(x^2-2x-3)|2x^3 + x^2 - 3x+ 5 \n" ); document.write( ": \n" ); document.write( "You should get 2x + 5: + Remainder \n" ); document.write( ": \n" ); document.write( "Decompose the remainder: \n" ); document.write( " \n" ); document.write( "Factor the denominator \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Since these fractions have the same denominator, their numerators have to be equal \n" ); document.write( "13x+20 = A(x+1) + B(x-3) \n" ); document.write( ": \n" ); document.write( "Let x = 3, then B drops out and we can solve for A: \n" ); document.write( "13(3) + 20 = A(3+1) + B(3-3) \n" ); document.write( ": \n" ); document.write( "39 + 20= A(4) + B(0) \n" ); document.write( ": \n" ); document.write( "59 = 4A \n" ); document.write( ": \n" ); document.write( "A = 59/4 \n" ); document.write( ": \n" ); document.write( "A = 14.75 \n" ); document.write( ": \n" ); document.write( "Let x = -1, then A drops out \n" ); document.write( "13(-1) + 20 = A(-1+1) + B(-1-3) \n" ); document.write( ": \n" ); document.write( "-13 + 20 = A(0) + B(-4) \n" ); document.write( ": \n" ); document.write( "7 = -4B \n" ); document.write( ": \n" ); document.write( "B = 7/-4 \n" ); document.write( ": \n" ); document.write( "B = -1.75 \n" ); document.write( ": \n" ); document.write( "The quotient and the partial fractions: \n" ); document.write( "(2x + 5) + \n" ); document.write( " \n" ); document.write( " |