document.write( "Question 995921: if x+1 is a factor of x^3+3x^2+kx+4, find the value of k. \n" ); document.write( "

Algebra.Com's Answer #614550 by ikleyn(52786) $\"\"$ $\"About$

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\n" ); document.write( "if x+1 is a factor of x^3+3x^2+kx+4, find the value of k.
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\n" ); document.write( "\n" ); document.write( "If x+1 is a factor of $\"x%5E3%2B3x%5E2%2Bkx%2B4\"$ , then x = -1 is the root of this polynomial.\r
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\n" ); document.write( "\n" ); document.write( "It means that if we substitute -1 instead of x into the polynomial, we get 0:\r
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\n" ); document.write( "\n" ); document.write( " $\"%28-1%29%5E3+%2B+3%28-1%29%5E2+%2B+k%2A%28-1%29+%2B+4\"$ = $\"0\"$ , or\r
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\n" ); document.write( "\n" ); document.write( "-1 + 3 - k + 4 = 0.\r
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\n" ); document.write( "\n" ); document.write( "It is the equation to determine k, and it gives\r
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\n" ); document.write( "\n" ); document.write( "k = -1 + 3 + 4 = 6.\r
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