document.write( "Question 78251This question is from textbook College Algebra
\n" ); document.write( ": Problem: Find all the real zeros of the polynomial. Use the quadratic formula if necessary.\r
\n" ); document.write( "\n" ); document.write( "P(x)= x^3 + 4x^2 + 3x -2\r
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\n" ); document.write( "\n" ); document.write( "I tried all the possible zeros with synthetic division and none came up as a zero. I think I am going wrong with division somewhere. Thank you. \n" ); document.write( "

Algebra.Com's Answer #56153 by rmromero(383) $\"\"$ $\"About$

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document.write( "Problem: Find all the real zeros of the polynomial. Use the quadratic formula if necessary.\r
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document.write( "P(x)= x^3 + 4x^2 + 3x -2\r
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document.write( "To get the possible zeros of the polynomials p/q can help us, where p= 2
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document.write( "it is the last term. q = 1, this is the coefficient of the first term\r
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document.write( "We will factor p and q
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document.write( "p = 1*2 and -1*-2
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document.write( "  = 1, 2, -1, -2\r
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document.write( "q = 1*1 and -1*-1
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document.write( "  = 1, -1\r
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document.write( "possible zeros p/q are 1, -1, 2, -2\r
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document.write( "Test using synthetic division which among them are the real zeros of the polynomial\r
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document.write( "1   |   1    4     3    -2
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document.write( "             1     5     8
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document.write( "        1    5     8    6    --- > not a real zero\r
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document.write( "-1  |   1   4    3    -2
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document.write( "           -1   -3     0
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document.write( "        1   3    0    -2    ==> Not a real zero\r
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document.write( "2  |   1    4    3    -2
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document.write( "            2    12   30
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document.write( "       1    6    15   28   ====> not a real zero\r
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document.write( "-2    |  1   4   3   -2
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document.write( "            -2  -4    2
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document.write( "         1   2  -1   0    ===> a Real zero\r
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document.write( "the factor now is (x + 2) (x^2 + 2x - 1)
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document.write( "                              |
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document.write( "                               --> we can use quadratic formula to get the factor for this where a = 1, b = 2 and c = -2\r
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document.write( "              \r
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document.write( "                  
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document.write( "               
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document.write( "                  \r
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document.write( "             \r
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document.write( "                       \r
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document.write( "               \r
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document.write( "               \r
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document.write( "There are 3 real zeros of the polynomial\r
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document.write( "   x= -2, \r
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document.write( "   , \r
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document.write( "     \r
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document.write( "Rmromero \n" );
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