document.write( "Question 818956: The question asks to find a quadratic equation whose solutions are +2i and -2i. How do you find this with no other information? \n" ); document.write( "

Algebra.Com's Answer #492881 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "find a quadratic equation whose solutions are +2i and -2i
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document.write( "The factor theorem states that a polynomial f(x) has a factor (x − k) if and only if f(k) = 0. 
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document.write( " f(x) = (x+2i)(x-2i) = x^2 + 4    |note  i^2 = -1
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document.write( "Check answer with FOIL
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document.write( "F	First terms    x^2
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document.write( "O	Outside terms  -2i
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document.write( "I	Inside terms   +2i
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document.write( "L	Last terms    -4(-1)
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