document.write( "Question 1150857: Please help me to solve question value of x and y when (x+yi)^2=5+4i
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Algebra.Com's Answer #772390 by math_helper(2461) $\"\"$ $\"About$

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An easy way to solve this is to use polar form of the complex number:\r
\n" ); document.write( "\n" ); document.write( "5+4i = $\"+%28sqrt%284%5E2%2B5%5E2%29%29e%5E%28i%2Atheta%29+\"$
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\n" ); document.write( "\n" ); document.write( "where $\"+theta+=+tan%5E-1%284%2F5%29+\"$ = 0.67474 radians to 5 decimal places
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\n" ); document.write( "\n" ); document.write( "5+4i = $\"+6.40312e%5E%28i%2A0.67474%29+\"$
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\n" ); document.write( "\n" ); document.write( "From here, take the square root of the leading coeffiient and divide $\"theta\"$ by two:
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\n" ); document.write( "\n" ); document.write( " $\"sqrt%285%2B4i%29+=+2.53044%2Ae%5E%28i%2A0.33737%29+\"$
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\n" ); document.write( "\n" ); document.write( "Using $\"+r%2Ae%5E%28i%2Atheta%29+=+r%2Acos%28theta%29+%2B+r%2Ai%2Asin%28theta%29+\"$ :

\n" ); document.write( " $\"sqrt%285%2B4i%29+=+2.38780+%2B+i%2A0.83759+\"$
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\n" ); document.write( "\n" ); document.write( "which gives you x and y by direct comparison.
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\n" ); document.write( "\n" ); document.write( "And of course, the negative of that answer, because (-a)^2 = (a)^2 \r
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