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The roots of an equation are x=-1 plus or minus I the equation is x^2+ ?

User BlueCat
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1 Answer

1 vote

Answer:

x^2+2x+2

Explanation:

If the roots of the equation are -1\pm i, then by the zero product rule:


x=-1\pm i \\\\x+1\pm i=0 \\\\(x+1+i)(x+1-i)=0\\\\x^2+x-ix+x+1-i+ix+i+1=0 \\\\x^2+2x+2=0

You can confirm this with the quadratic equation:


x=(-2\pm√(4-8))/(2)=(-2\pm 4i)/(2)=-1\pm i

Hope this helps!

User Sheridan Bulger
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