document.write( "Question 1028737: Please help me! Thanks (:\r
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\n" ); document.write( "\n" ); document.write( "Approximate the zeros of the function. Round to the nearest tenth. \r
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\n" ); document.write( "\n" ); document.write( "1.) y=x^2-7x+7\r
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\n" ); document.write( "\n" ); document.write( "2.) y=-2x^2-9x+10\r
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Algebra.Com's Answer #643908 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
We use Newton's method to approximate zeros
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\n" ); document.write( "x(n+1) = x(n) - (f(x(n)) / f'(x(n)))
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\n" ); document.write( "1) y = x^2-7x+7
\n" ); document.write( "Consider the graph of this equation
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\n" ); document.write( "The zeros are close to 1 and 6, I will show you how to find the zero close to 1. All others follow the same procedure.
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\n" ); document.write( "Calculate f'
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\n" ); document.write( "f' = 2x-7
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\n" ); document.write( "Let x(0) = 1, then
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\n" ); document.write( "x(1) = x(0) - (f(x(0)) / f'(x(0))
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\n" ); document.write( "x(1) = 1 - (1 / -5) = 1.2
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\n" ); document.write( "x(2) = 1.2 - (0.04 / -4.6) approx 1.2
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\n" ); document.write( "Since x(2) = x(1), there is no point in continuing
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\n" ); document.write( "f(1.2) = 0.04 approximately 0.0, therefore
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\n" ); document.write( "x = 1.2 is a good approximation for a zero
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