document.write( "Question 1159546: The function f is given by f(x)=x^3+2x^2+ax-8 where a is constant.when f(x) is divided by (x-2) the remainder is -6.
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Algebra.Com's Answer #782596 by MathLover1(20850)\"\" \"About 
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given:\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=x%5E3%2B2x%5E2%2Bax-8\" where \"a\" is constant.when\"+f%28x%29\" is divided by\"+%28x-2%29\" the remainder is \"-6\".\r
\n" ); document.write( "\n" ); document.write( "first find \"a\":\r
\n" ); document.write( "\n" ); document.write( ".........(\"x%5E2%2B4x%2B%28a%2B8%29\"
\n" ); document.write( "\"%28x-2%29\" |\"x%5E3%2B2x%5E2%2Bax-8\"
\n" ); document.write( ".........\"x%5E3-2x%5E2\"............subtract
\n" ); document.write( "...............\"4x%5E2%2Bax\"
\n" ); document.write( "...............\"4x%5E2-8x\"............subtract
\n" ); document.write( ".......................\"ax%2B8x\".......
\n" ); document.write( ".......................\"%28a%2B8%29x\"
\n" ); document.write( "........................\"%28a%2B8%29x-8\"
\n" ); document.write( ".......................\"%28a%2B8%29x-2%28a%2B8%29\"..........subtract
\n" ); document.write( "..................................\"-8%2B2%28a%2B8%29\".......
\n" ); document.write( "..................................\"-8%2B2a%2B8\".......
\n" ); document.write( ".........................................\"2a\".........reminder\r
\n" ); document.write( "\n" ); document.write( "if given the remainder is \"-6\", we have\"+2a=-6+\"=> \"a=-6\"\r
\n" ); document.write( "\n" ); document.write( "then quotient is \"x%5E2%2B4x%2B%28a%2B8%29=x%5E2%2B4x-3%2B8=x%5E2%2B4x%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "and \"+f%28x%29=x%5E3%2B2x%5E2-3x-8+\"\r
\n" ); document.write( "\n" ); document.write( "=> since \"%28x%5E2+%2B+4+x+%2B+5%29%28x+-+2%29=x%5E3+%2B+2+x%5E2+-+3+x+-+10\"\r
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\n" ); document.write( "\n" ); document.write( "subtract it from \"x%5E3%2B2x%5E2-3x-8\" to find new reminder\r
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\n" ); document.write( "\n" ); document.write( "=> reminder is \"2\"\r
\n" ); document.write( "\n" ); document.write( "and \"x%5E3%2B2x%5E2-3x-8+=%28x%5E2+%2B+4+x+%2B+5%29%28x+-+2%29%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "also given that:\r
\n" ); document.write( "\n" ); document.write( "\"+f%28x%29\" can be written in the form \"%28x%2B1%29%28x%5E2%2Bbx%2Bc%29\" where\"+b+\"and \"c\" are constants\r
\n" ); document.write( "\n" ); document.write( "find the values of \"b\" and \"c\"\r
\n" ); document.write( "\n" ); document.write( "\"+f%28x%29=x%5E3%2B2x%5E2-3x-8+\"=>
\n" ); document.write( "\"+x%5E3%2B2x%5E2-3x-8=%28x%2B1%29%28x%5E2%2Bbx%2Bc%29+\".....expand right side\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E3%2B2x%5E2-3x-8=bx%5E2+%2B+bx+%2B+cx+%2B+c+%2B+x%5E3+%2B+x%5E2\"
\n" ); document.write( "\"+x%5E3%2B2x%5E2-3x-8=x%5E3%2B+x%5E2%2B+bx%5E2+%2B+bx+%2B+cx+%2B+c++\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E3%2B2x%5E2-3x-8=x%5E3%2B+%281%2B+b%29x%5E2+%2B+%28b+%2B+c%29x+%2B+c++\".....compare coefficients\r
\n" ); document.write( "\n" ); document.write( "\"2=%281%2B+b%29\"
\n" ); document.write( "\"b=2-1\"
\n" ); document.write( "\"b=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28b+%2B+c%29=-3\"
\n" ); document.write( "\"1%2Bc=-3\"
\n" ); document.write( "\"c=-4\"\r
\n" ); document.write( "\n" ); document.write( "substitute in\r
\n" ); document.write( "\n" ); document.write( "\"x%5E3%2B+%281%2B+b%29x%5E2+%2B+%28b+%2B+c%29x+%2B+c++\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E3%2B+%281%2B+1%29x%5E2+%2B+%281+-4%29x+-4++\"
\n" ); document.write( "\"+x%5E3%2B+2x%5E2+%2B++-3x+-4++\"\r
\n" ); document.write( "\n" ); document.write( "subtract \r
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "\n" ); document.write( "so, new reminder is \"-4\", and\r
\n" ); document.write( "\n" ); document.write( "\"x%5E3+%2B+2+x%5E2+-+3+x+-+8+=+%28x%5E2+%2B+x+-+4%29+%28x+%2B+1%29++-4\"\r
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