document.write( "Question 35491: given x + iy form, write in polar form: 5-i \n" ); document.write( "
Algebra.Com's Answer #21643 by AnlytcPhil(1806)\"\" \"About 
You can put this solution on YOUR website!
given x + iy form, write in polar form: 5-i\r\n" );
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document.write( "5 - i\r\n" );
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document.write( "A + Bi is represented by the vector whose tail is at (0,0)\r\n" );
document.write( "and whose head is at (A,B)\r\n" );
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document.write( "5 - i, then, is represented by the vector whose tail is at (0,0)\r\n" );
document.write( "and whose head is at (5,-1)\r\n" );
document.write( "\"+graph%28+200%2C+200%2C+-5%2C+5%2C+-5%2C+5%2C+-sqrt%28x%5E2%2Fx%29sqrt%28x%29%2F5%29+\"(5,-1) \r\n" );
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document.write( "so x=5, y=-1  \r\n" );
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document.write( "q = tan-1(y/x) in Q4 = tan-1(-1/5) in Q4. By calculator,\r\n" );
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document.write( "tan-1(1/5) = 11.3°, so to get the angle in Q4 we subtract from 360°\r\n" );
document.write( "and get q = 348.7°\r\n" );
document.write( "     _____    __________    ____    __\r\n" );
document.write( "r = Öx²+y² = Ö(5)²+(-1)² = Ö25+1 = Ö26\r\n" );
document.write( "                    __\r\n" );
document.write( "r(cosq + i·sinq) = Ö26(cos348.7° + i·sin348.7°)\r\n" );
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document.write( "Edwin McCravy\r\n" );
document.write( "AnlytcPhil@aol.com
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