document.write( "Question 61715: Can you help me please\r
\n" ); document.write( "\n" ); document.write( "Find all three zeros of f(x)=x^3-4X^2+13x+50 given that 3+4i is a zero \r
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Algebra.Com's Answer #42503 by ankor@dixie-net.com(22740)\"\" \"About 
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Find all three zeros of f(x)=x^3-4X^2+13x+50 given that 3+4i is a zero
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\n" ); document.write( "Find the expression for 3 + 4i, reverse the procedure of completing the square:
\n" ); document.write( "x = 3 + 4i
\n" ); document.write( "x - 3 = 4i
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\n" ); document.write( "Square both sides
\n" ); document.write( "(x-3)^2 = 4i * 4i
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\n" ); document.write( "x^2 - 6x + 9 = 16(i^2)
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\n" ); document.write( "Remember i^2 = -1
\n" ); document.write( "x^2 - 6x + 9 = 16(-1)
\n" ); document.write( "x^2 - 6x + 9 = -16
\n" ); document.write( "x^2 - 6x + 9 + 16 = 0
\n" ); document.write( "x^2 - 6x + 25 = 0
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\n" ); document.write( "We can see that the last term is 50 so the above expression has to multiplied by the factor (x + 2) to get x^3 - 4X^2 + 13x + 50
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\n" ); document.write( "The 3 zeros: -2, 3+4i, 3-4i
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