document.write( "Question 127200: One root of the function y=x^2-10x+k is 5+2isqrt3. What is the value of k???? \n" ); document.write( "
Algebra.Com's Answer #93191 by stanbon(75887)\"\" \"About 
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One root of the function y=x^2-10x+k is 5+2isqrt3. What is the value of k????
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\n" ); document.write( "If 5+2sqrt(3)i is a root, so is 5-2sqrt(3)i.
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\n" ); document.write( "Then the following product is a factor of the given polynomial:
\n" ); document.write( "(x-(5+2sqrt(3)i)(x-(5-2sqrt(3)i)\r
\n" ); document.write( "\n" ); document.write( "= ((x-5)-2sqrt(3)i)((x-5)+2sqrt(3)i)
\n" ); document.write( "Comment: Notice that the factors are in the form (a-b)(a+b).
\n" ); document.write( "So the product is a^2-b^2
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\n" ); document.write( "\n" ); document.write( "= (x-5)^2 -(2sqr(3)i)^2\r
\n" ); document.write( "\n" ); document.write( "= x^2-10x+25+12\r
\n" ); document.write( "\n" ); document.write( "= x^2-12x+37\r
\n" ); document.write( "\n" ); document.write( "Comparing that to the original polynominal you see that
\n" ); document.write( "k = 37
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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