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Answer :

We know that a root of a quadratic function is a value of x that makes the function equal to 0.

So,

[tex]\begin{gathered} \text{ if (1 + i) is a root of }y=x^2+2x+2 \\ \end{gathered}[/tex]

it must be fulfilled that,

[tex]f(1+i)=0[/tex]

Now, we must replace (1 + i) in the function

[tex]\begin{gathered} (1+i)^2+2(1+i)+2 \\ \\ \\ \end{gathered}[/tex]

solving the parentheses,

[tex]=1+2i+i^2+2+2i+2[/tex]

Using that i^2 = -1

[tex]=1+2i-1+2+2i+2[/tex]

grouping similar terms

[tex]\begin{gathered} =(1-1+2+2)+(2i+2i) \\ \end{gathered}[/tex]

Finally, simplifying

[tex]=4+4i[/tex]

We can see that

[tex]4+4i\ne0[/tex]

So, (1 + i) is not a root of the equation.

The statement is false.

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