document.write( "Question 117478: decompose into a partial fraction\r
\n" ); document.write( "\n" ); document.write( "2x^3+x^2-3x+5 / x^2-2x-3
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Algebra.Com's Answer #85998 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Decompose into a partial fraction
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\n" ); document.write( "\"%282x%5E3%2Bx%5E2-3x%2B5%29+%2F+%28x%5E2-2x-3%29\"
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\n" ); document.write( "Numerator degree is greater than the denominator:
\n" ); document.write( "Divide using long division:
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\n" ); document.write( "(x^2-2x-3)|2x^3 + x^2 - 3x+ 5
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\n" ); document.write( "You should get 2x + 5: + Remainder\"%2813x%2B20%29%2F%28x%5E2-2x-3%29\"
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\n" ); document.write( "Decompose the remainder:
\n" ); document.write( "\"%2813x%2B20%29%2F%28x%5E2-2x-3%29\"
\n" ); document.write( "Factor the denominator
\n" ); document.write( "\"%2813x%2B20%29+%2F%28%28x-3%29%28x%2B1%29%29\" = \"A%2F%28%28x-3%29%29\" + \"B%2F%28%28x%2B1%29%29\" = \"%28A%28x%2B1%29+%2B+B%28x-3%29%29%2F%28%28x-3%29%28x%2B1%29%29\"
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\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)
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\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)
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\n" ); document.write( "39 + 20= A(4) + B(0)
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\n" ); document.write( "59 = 4A
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\n" ); document.write( "A = 59/4
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\n" ); document.write( "A = 14.75
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\n" ); document.write( "Let x = -1, then A drops out
\n" ); document.write( "13(-1) + 20 = A(-1+1) + B(-1-3)
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\n" ); document.write( "-13 + 20 = A(0) + B(-4)
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\n" ); document.write( "7 = -4B
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\n" ); document.write( "B = 7/-4
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\n" ); document.write( "B = -1.75
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\n" ); document.write( "The quotient and the partial fractions:
\n" ); document.write( "(2x + 5) + \"14.75%2F%28%28x-3%29%29\" + \"%28-1.75%29%2F%28%28x%2B1%29%29\"
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