document.write( "Question 173218: What does the product (4+7i)(2-5i) equal?\r
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\n" ); document.write( "\n" ); document.write( "What does the quotient (1+4i)/(5-2i) equal?
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Algebra.Com's Answer #128050 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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\n" ); document.write( "\n" ); document.write( "\"%284%2B7i%29%2A%282-5i%29\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%284%29%282%29%2B%284%29%28-5i%29%2B%287i%29%282%29%2B%287i%29%28-5i%29\" FOIL.\r
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\n" ); document.write( "\n" ); document.write( "\"8-20i%2B14i-35i%5E2\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"8-20i%2B14i-35%28-1%29\" Replace \"i%5E2\" with \"-1\". Note: \"i%5E2=-1\".\r
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\n" ); document.write( "\n" ); document.write( "\"8-20i%2B14i%2B35\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"43-6i\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So \"%284%2B7i%29%2A%282-5i%29=43-6i\".\r
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\n" ); document.write( "\n" ); document.write( "So the expression is now in standard form \"a%2Bbi\" where \"a=43\" and \"b=-6\"\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "\"%281%2B4i%29%2F%285-2i%29\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28%281%2B4i%29%2F%285-2i%29%29%28%285%2B2i%29%2F%285%2B2i%29%29\" Multiply the fraction by \"%285%2B2i%29%2F%285%2B2i%29\" (which is the complex conjugate of the denominator).\r
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\n" ); document.write( "\n" ); document.write( "\"%28%281%2B4i%29%285%2B2i%29%29%2F%28%285-2i%29%285%2B2i%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( "\"%285%2B2i%2B20i%2B8i%5E2%29%2F%2825%2B10i-10i-4i%5E2%29\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"%28-3%2B22i%29%2F%2829%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-3%2F29%2B%2822%2F29%29%2Ai\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "So \"%281%2B4i%29%2F%285-2i%29=-3%2F29%2B%2822%2F29%29%2Ai\".\r
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\n" ); document.write( "\n" ); document.write( "So the expression is now in standard form \"a%2Bbi\" where \"a=-3%2F29\" and \"b=22%2F29\"
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