document.write( "Question 192058: The complex number 13 + i can be factored into the product of 1 + 2i and what other complex number? \n" ); document.write( "
Algebra.Com's Answer #144116 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Since 13 + i can be factored where one factor is \"1%2B2i\", this means that \r
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\n" ); document.write( "\n" ); document.write( "\"13+%2B+i=%281%2B2i%29%2Ax\" where \"x\" is the other factor\r
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\n" ); document.write( "\n" ); document.write( "\"13+%2B+i=%281%2B2i%29%2Ax\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%2813+%2B+i%29%2F%281%2B2i%29=x\" Divide both sides by \"1%2B2i\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2813+%2B+i%29%2F%281%2B2i%29\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "So the other factor is \"%2813+%2B+i%29%2F%281%2B2i%29\". Let's simplify \"%2813+%2B+i%29%2F%281%2B2i%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2813%2Bi%29%2F%281%2B2i%29\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28%2813%2Bi%29%2F%281%2B2i%29%29%28%281-2i%29%2F%281-2i%29%29\" Multiply the fraction by \"%281-2i%29%2F%281-2i%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28%2813%2Bi%29%281-2i%29%29%2F%28%281%2B2i%29%281-2i%29%29\" Combine the fractions.\r
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\n" ); document.write( "\n" ); document.write( " FOIL the numerator.\r
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\n" ); document.write( "\n" ); document.write( " FOIL the denominator.\r
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\n" ); document.write( "\n" ); document.write( "\"%2813-26i%2Bi-2i%5E2%29%2F%281-2i%2B2i-4i%5E2%29\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"%2815-25i%29%2F%285%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%2815%29%2F%285%29%2B%28%28-25%29%2F%285%29%29i\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"3-5i\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So \"%2813%2Bi%29%2F%281%2B2i%29=3-5i\".\r
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\n" ); document.write( "\n" ); document.write( "Since \"x=%2813%2Bi%29%2F%281%2B2i%29\", this means that \"x=3-5i\"\r
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\n" ); document.write( "\n" ); document.write( "So the other factor is \"3-5i\"\r
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\n" ); document.write( "\n" ); document.write( "So this means that \"13%2Bi=%281%2B2i%29%283-5i%29\"\r
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\n" ); document.write( "\n" ); document.write( "Note: you can check this by multiplying the given factor \"1%2B2i\" by \"3-5i\" to get \"13%2Bi\"\r
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