document.write( "Question 937988: I'm trying to figure out how to find \"Complex Zeros of Quadratic Functions\" but the Holt McDougal video lesson isn't helping whatsoever and I've researched as much as I could. I'm trying to find the zeros of \"f(x)=x²+2x+3\" and the video says the answer is x=6+2i√3. This involves imaginary numbers. \n" ); document.write( "
Algebra.Com's Answer #571338 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
What happens if you put the function into a graph?\r
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\n" ); document.write( "\n" ); document.write( "You can try the old slow way of making a data table for getting several points and then plotting them, and try to guess the ROOTS or ZEROS.\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28300%2C300%2C-6%2C6%2C-6%2C6%2Cx%5E2%2B2x%2B3%29\"\r
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\n" ); document.write( "\n" ); document.write( "This parabola does not cross nor touch the x-axis, and therefore has NO REAL ZEROS. \r
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\n" ); document.write( "\n" ); document.write( "But the function DOES have Complex zeros.
\n" ); document.write( "Accept a number, i such that:
\n" ); document.write( "\"highlight_green%28i%5E2=-1%29\".
\n" ); document.write( "Raising this to the \"1%2F2\" power, you find that \"i=sqrt%28-1%29\" or \"i=-sqrt%28-1%29\".\r
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\n" ); document.write( "\n" ); document.write( "NEXT, set f(x) to 0, and SOLVE FOR x, using Completing the Square.
\n" ); document.write( "\"x%5E2%2B2x%2B3=0\"
\n" ); document.write( "\"x%5E2%2B2x%2B%282%2F2%29%5E2%2B3=%282%2F2%29%5E2\", the full expression shown so it will be less of a mystery
\n" ); document.write( "\"x%5E2%2B2x%2B1%2B3=1\"
\n" ); document.write( "\"%28x%5E2%2B2x%2B1%29%2B3=1\"
\n" ); document.write( "\"%28x%2B1%29%5E2%2B3=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B1%29%5E2=-2\"\r
\n" ); document.write( "\n" ); document.write( "\"x%2B1=0%2B-+sqrt%28-2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-1%2B-+sqrt%28-2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-1%2B-+sqrt%28-1%2A2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-1%2B-+sqrt%28-1%29sqrt%282%29\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28highlight%28x=-1%2B-+i%2Asqrt%282%29%29%29\"
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