document.write( "Question 1194781: Given 2x² = -8, x is
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Algebra.Com's Answer #827056 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Given  2x² = -8  IMPLIES\r\n" );
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document.write( "        x^2 = -4     (which is -8/2),\r\n" );
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document.write( "and it means that x can not be real number.\r\n" );
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document.write( "This equation HAS NO solutions in real numbers.\r\n" );
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document.write( "It has solutions in complex number domain.\r\n" );
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document.write( "In complex number domain, equation \r\n" );
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document.write( "    x^2 = -4\r\n" );
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document.write( "has two roots\r\n" );
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document.write( "    x =  = +/- 2i,\r\n" );
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document.write( "where  \" i \"  is complex imaginary units   i = .\r\n" );
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document.write( "So, again, the original equation has no real roots;\r\n" );
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document.write( "it has two complex roots   2i  and  -2i.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On complex numbers, see introductory lessons\r
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\n" ); document.write( "\n" ); document.write( "    - Solved problems on taking roots of complex numbers\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on arithmetic operations on complex numbers\r
\n" ); document.write( "\n" ); document.write( "    - Solved problem on taking square root of complex number\r
\n" ); document.write( "\n" ); document.write( "    - Solving polynomial equations in complex domain \r
\n" ); document.write( "\n" ); document.write( "    - Miscellaneous problems on complex numbers\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook on ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Complex numbers\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
\n" ); document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r
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