document.write( "Question 175743This question is from textbook Algebra 2 (McDougal Littel)
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\n" ); document.write( "f(x) = x4 + x3 + 2x2 + 4x - 8
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Algebra.Com's Answer #130836 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "f(x) = x4 + x3 + 2x2 + 4x - 8\r\n" );
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document.write( "Factor by grouping. \r\n" );
document.write( "First rearrange the terms:\r\n" );
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document.write( "f(x) = x4 + 2x2 - 8 + x3 + 4x\r\n" );
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document.write( "Factor the first three terms\r\n" );
document.write( "Factor x out of the last two\r\n" );
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document.write( "f(x) = (x2 + 4)(x2 - 2) + x(x2 + 4)\r\n" );
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document.write( "Factor out {x2 + 4)\r\n" );
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document.write( "f(x) = (x2 + 4)[(x2 - 2) + x]\r\n" );
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document.write( "Remove parentheses inside bracket\r\n" );
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document.write( "f(x) = (x2 + 4)[x2 - 2 + x]\r\n" );
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document.write( "Rearrange the terms in the bracket,\r\n" );
document.write( "and change the bracket to parentheses:\r\n" );
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document.write( "f(x) = (x2 + 4)(x2 + x - 2)\r\n" );
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document.write( "Factor the second parentheses:\r\n" );
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document.write( "f(x) = (x2 + 4)(x + 2)(x - 1)\r\n" );
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document.write( "Now we set that = 0\r\n" );
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document.write( "(x2 + 4)(x + 2)(x - 1) = 0\r\n" );
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document.write( "Using the zero factor principle:\r\n" );
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document.write( "x2 + 4 = 0        x + 2 =  0         x - 1 = 0\r\n" );
document.write( "    x2 = -4           x = -2             x = 1\r\n" );
document.write( "     x = ±2i\r\n" );
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document.write( "The solutions are 2i, -2i, -2, and 1\r\n" );
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document.write( "Edwin
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