The given expression is
![x^2+1](https://img.qammunity.org/2023/formulas/mathematics/college/lu5dt8v7tx1dvk48t3pkp6u6y8t3aui37m.png)
We can not factorize this expression bt the normal factorizing ways
Because it is a binomial with + as a middle sign can not be distributed into 2 factors
Then there is no factorizing for the given binomial
If the sign between the two terms is (-), then we can factorize it into two same factors with different middle sign
We can use the complex numbers to factorize it
![\begin{gathered} x^2=(x)(x) \\ 1=(i)(-i) \\ (x)(i)+(x)(-i)=(xi)-(xi)=0 \\ (x+i)(x-i) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/hvnqum01ci99ba5pddnjxfnguzs77l2jql.png)
Then the factors are (x + i) and (x - i)
![x^2+1=(x+i)(x-i)](https://img.qammunity.org/2023/formulas/mathematics/college/ljm88iq71f7u14fz8tvms7byuygbtm320s.png)