document.write( "Question 144741: Multiply the complex numbers.\r
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\n" ); document.write( "\n" ); document.write( "(5 + 2i)(2 - i)\r
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Algebra.Com's Answer #105471 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"%285%2B2i%29%282-i%29\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "Remember, when you FOIL an expression, you follow this procedure:\r
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\n" ); document.write( "\n" ); document.write( "\"%28highlight%285%29%2B2i%29%28highlight%282%29-i%29\" Multiply the First terms:\"%285%29%2A%282%29=10\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28highlight%285%29%2B2i%29%282%2Bhighlight%28-i%29%29\" Multiply the Outer terms:\"%285%29%2A%28-1i%29=-5i\"\r
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\n" ); document.write( "\n" ); document.write( "\"%285%2Bhighlight%282i%29%29%28highlight%282%29-i%29\" Multiply the Inner terms:\"%282i%29%2A%282%29=4i\"\r
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\n" ); document.write( "\n" ); document.write( "\"%285%2Bhighlight%282i%29%29%282%2Bhighlight%28-i%29%29\" Multiply the Last terms:\"%282i%29%2A%28-1i%29=-2i%5E2=-2%28-1%29=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"10-5i%2B4i%2B2\" Now collect every term to make a single expression\r
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\n" ); document.write( "\n" ); document.write( "\"12-i\" Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
\n" ); document.write( "\n" ); document.write( "So \"%285%2B2i%29%282-i%29\" foils and simplifies to \"12-i\"\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"%285%2B2i%29%282-i%29=12-i\"\r
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