document.write( "Question 736989: 5-i / 4-3i \n" ); document.write( "
Algebra.Com's Answer #852689 by ikleyn(53313)\"\" \"About 
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document.write( "You are given a fraction of complex numbers  \"%285-i%29%2F%284-3i%29\".\r\n" );
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document.write( "They want you transform it to the standard form complex number.\r\n" );
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document.write( "To do it, multiply the numerator and denominator by the complex number,\r\n" );
document.write( "which is conjugate to the denominator of the given fraction.\r\n" );
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document.write( "So, you write\r\n" );
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document.write( "    \"%285-i%29%2F%284-3i%29\" = \"%28%285-i%29%2F%284-3i%29%29%2A%28%284%2B3i%29%2F%284%2B3i%29%29\" = \"%28%285-i%29%2A%284%2B3i%29%29%2F%28%284-3i%29%2A%284%2B3i%29%29\".\r\n" );
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document.write( "Now, to avoid a mess, let's work with the numerator and the denominator separately.\r\n" );
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document.write( "In the numerator, you have\r\n" );
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document.write( "    (5-i)*(4+3i) = 20 + 15i - 4i - 3i^2 = 20 + 11i - 3*(-1) = 20 + 3 + 11i = 23 + 11i.\r\n" );
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document.write( "In the denominator, you have the product of a complex number (4-3i) and its conjugate (4+3i),\r\n" );
document.write( "which is a real number\r\n" );
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document.write( "    (4-3i)*(4+3i) = 4^2 + 3^2 = 16 + 9 = 25.\r\n" );
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document.write( "Thus, the ratio  \"%285-i%29%2F%284-3i%29\"  is\r\n" );
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document.write( "    \"%285-i%29%2F%284-3i%29\" = \"%2823%2B11i%29%2F25\" = \"92%2F100+%2B+%2844%2F100%29i\" = 0.92 + 0.44i.\r\n" );
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document.write( "It is a standard form of a complex number.\r\n" );
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document.write( "At this point, the assignment is complete.\r\n" );
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document.write( "ANSWER.  \"%285-i%29%2F%284-3i%29\" = \"23%2F25+%2B+%2811%2F25%29%2Ai\".\r\n" );
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document.write( "         Or, which is the same,  \"%285-i%29%2F%284-3i%29\" = 0.92 + 0.44*i.\r\n" );
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