document.write( "Question 245751: I need to find the zeros of f(x)=x^2+2ix-3.
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Algebra.Com's Answer #179460 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Just treat this quadratic as you normally would, but make sure to follow the rules of complex arithmetic.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B2ix-3=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2%2B2ix-3\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=2i\", and \"C=-3\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%282i%29+%2B-+sqrt%28+%282i%29%5E2-4%281%29%28-3%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=2i\", and \"C=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2i+%2B-+sqrt%28+-4-4%281%29%28-3%29+%29%29%2F%282%281%29%29\" Square \"2i\" to get \"%282i%29%5E2=%282i%29%282i%29=4i%5E2=4%28-1%29=-4\"\r
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\n" ); document.write( "\n" ); document.write( "Note: Since \"i=sqrt%28-1%29\", \"i%5E2=%28sqrt%28-1%29%29%5E2=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2i+%2B-+sqrt%28+-4%2B12+%29%29%2F%282%281%29%29\" Multiply -4, 1 and -3 to get \"-4%281%29%28-3%29=12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2i+%2B-+sqrt%28+-4%2B12+%29%29%2F%282%29\" Multiply 2 and 1 to get 2.\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2i+%2B-+sqrt%28+8+%29%29%2F%282%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2i+%2B-+2%2Asqrt%28+2+%29%29%2F%282%29\" Simplify the square root.\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-i+%2B-+sqrt%28+2+%29\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-i+%2B+sqrt%28+2+%29\" or \"x+=+-i+-+sqrt%28+2+%29\" Break up the 'plus/minus'\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+-i+%2B+sqrt%28+2+%29\" or \"x+=+-i+-+sqrt%28+2+%29\"
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