document.write( "Question 977664: Find all real zeros of the function y=x^3 - 2 x^2 - 25 x +50. \n" ); document.write( "
Algebra.Com's Answer #599227 by ikleyn(52787)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Solution 1\r
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\n" ); document.write( "\n" ); document.write( "The polynomial  \"y\" = \"x%5E3+-+2x%5E2+-+25x+%2B50\"  has the real root  \"x\" = \"2\". \r
\n" ); document.write( "\n" ); document.write( "Indeed,  it is easy to check:  \"2%5E3+-2%2A2%5E2+-+25%2A2+%2B+50\" = \"0\".\r
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\n" ); document.write( "\n" ); document.write( "Hence,  this polynomial can be factored \r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3+-+2x%5E2+-+25+x+%2B50\" = \"%28x-2%29\".\"f%28x%29\" \r
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\n" ); document.write( "\n" ); document.write( "with he linear factor  \"x-2\",  where  \"f%28x%29\"  is a quadratic polynomial. \r
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\n" ); document.write( "\n" ); document.write( "To find  \"f%28x%29\",  divide the polynomial  \"x%5E3+-+2x%5E2+-+25x+%2B50\"  by  \"x-2\"  (long division). \r
\n" ); document.write( "\n" ); document.write( "If you perform this division,  you will get \r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3+-+2x%5E2+-+25x+%2B50\" = \"%28x-2%29\".\"%28x%5E2+-+25%29\".\r
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\n" ); document.write( "\n" ); document.write( "Hence,  two other roots of the given polynomial are the roots of the quadratic polynomial  \"x%5E2+-+25\",  i.e.  \"x%5B1%5D\" = \"5\"  and  \"x%5B2%5D\" = \"-5\".\r
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\n" ); document.write( "\n" ); document.write( "Answer.  The roots of the given polynomial  \"x%5E3+-+2x%5E2+-+25x+%2B50\"  are  2,  5  and  -5.\r
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\n" ); document.write( "\n" ); document.write( "Solution 2\r
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\n" ); document.write( "\n" ); document.write( "You can get factoring the polynomial  \"x%5E3+-+2+x%5E2+-+25+x+%2B50\"  by grouping its terms:\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3+-+2x%5E2+-+25x+%2B50\" = \"%28x%5E3+-+2x%5E2%29\" - \"%2825x+-50%29\" = \"x%5E2%28x-2%29\" - \"25%28x-2%29\" = \"%28x%5E2-25%29%2A%28x-2%29\". \r
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\n" ); document.write( "\n" ); document.write( "It gives you the same roots. \r
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