document.write( "Question 707573: Write an equation for a cubic polynomial p(x) with leading coefficient -1 whose graph passes through the point (2, 8) and is tangent to the x-axis at the origin. \n" ); document.write( "
Algebra.Com's Answer #435754 by josgarithmetic(39620)\"\" \"About 
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\"p%28x%29=-x%5E3%2Bbx%5E2%2Bcx%2Bd\"\r
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\n" ); document.write( "\n" ); document.write( "derivative of p(0) must be zero because of tangent at the origin. Taking derivative, setting it equal zero, seems c=0.\r
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\n" ); document.write( "\n" ); document.write( "p(2)=8, so carrying this through did not seem to help. 8=-8+4b+d, not too useful.\r
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\n" ); document.write( "\n" ); document.write( "Point (0,0) must satisfy our p(x) polynomial, so \"0=-0%5E3%2Bb%2A0%5E2%2Bd\",
\n" ); document.write( "apparantly d=0.\r
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\n" ); document.write( "\n" ); document.write( "So far we seem to have \"p%28x%29=-x%5E3%2Bbx%5E2\".
\n" ); document.write( "Let's try point (2,8) again.
\n" ); document.write( "\"p%28x%29=-%28x%5E2%29%28x-b%29\", also.
\n" ); document.write( "Using the point, \"8=-%282%29%5E2%2A%282-b%29\"
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\n" ); document.write( "b=4\r
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\n" ); document.write( "\n" ); document.write( "THIS should work well: \"p%28x%29=-%28x%5E2%29%28x-4%29\"
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