document.write( "Question 978698: z^(4)-z^(2)-2z+2
\n" ); document.write( "Please could someone help me with the last part of this question.\r
\n" ); document.write( "\n" ); document.write( "Write the following polynomial as products of linear factors:\r
\n" ); document.write( "\n" ); document.write( "z^(4)-z^(2)-2z+2\r
\n" ); document.write( "\n" ); document.write( "My try so far:\r
\n" ); document.write( "\n" ); document.write( "(z-1)(z^3+z^2-2)
\n" ); document.write( "(z-1)(z-1)(z^2+z+2)\r
\n" ); document.write( "\n" ); document.write( "From here I tried to use the quadratic formula and got:
\n" ); document.write( "Z=(-1+ sq rt 7)/2 or Z=(-1- sq rt 7)/2\r
\n" ); document.write( "\n" ); document.write( "The answer in the book is:\r
\n" ); document.write( "\n" ); document.write( "(z-1)^2 (z+1-i)(z+1+i)\r
\n" ); document.write( "\n" ); document.write( "Could anyone tell me where I went wrong?\r
\n" ); document.write( "\n" ); document.write( "Thank you for your time in advance.
\n" ); document.write( "

Algebra.Com's Answer #600075 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
First try check for root of 1 gives \"%28z-1%29%28z%5E3%2Bz%5E2-2%29\". Be sure that your dividend of synthetic division shows ALL degrees of z.\r
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\n" ); document.write( "\n" ); document.write( "continuing, again if root of 1 is checked, you find factorization \"%28z-1%29%28z-1%29%28z%5E2%2B2z%2B2%29\". You might have made a visual omission on paper or through keyboard, or maybe forgot about accounting for degrees of z in the division process.\r
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\n" ); document.write( "\n" ); document.write( "NOW to deal with the quadratic factor,
\n" ); document.write( "roots are \"%28-2%2B-+sqrt%284-4%2A2%29%29%2F2\"
\n" ); document.write( "\"-1%2B-+i\".\r
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\n" ); document.write( "\n" ); document.write( "To conitnue,
\n" ); document.write( "\"%28z-1%29%5E2%28z-%28-1-i%29%29%28x-%28-1%2Bi%29%29\", and you simply simplify this obviously complex factorization or keep as linear and quadratic factorization...
\n" ); document.write( "\"%28z-1%29%5E2%28z%2B1%2Bi%29%28z%2B1-i%29\"
\n" ); document.write( "\"highlight%28%28z-1%29%5E2%28%28z%2B1%29%2Bi%29%28%28z%2B1%29-i%29%29\"
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\n" ); document.write( "Either you want it that way, or you want ...
\n" ); document.write( "\"highlight%28%28z-1%29%5E2%28z%5E2%2B2z%2B2%29%29\".
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