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Find the quadratic equation with the roots indicated.{5 +/- i square root of 2}

Find the quadratic equation with the roots indicated.{5 +/- i square root of 2}-example-1
User Yodit
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1 Answer

14 votes
14 votes

Solution:

Given:


5\pm i√(2)

The roots of the quadratic equation are;


\begin{gathered} x=5\pm i√(2) \\ x=5+i√(2)\text{ OR }x=5-i√(2) \\ \\ The\text{ factors from the root are:} \\ (x-5-i√(2))=0\text{ OR }(x-5+i√(2))=0 \\ \\ As\text{ a quadratic equation:} \\ (x-5-i√(2))(x-5+i√(2))=0 \end{gathered}

Expanding the factors further;


\begin{gathered} (x-5-i√(2))(x-5+i√(2))=0 \\ x^2-5x+ix√(2)-5x+25-5i√(2)-ix√(2)+5i√(2)+2=0 \\ Collecting\text{ the like terms and simplifying further:} \\ x^2-5x-5x+ix√(2)-ix√(2)-5i√(2)+5i√(2)+25+2=0 \\ x^2-10x+27=0 \end{gathered}

Therefore, the quadratic equation is;


x^2-10x+27=0

User Dimakura
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