# Hiii can you pls help me what is the definition domain of (1+x)/(1+x^2)?

Oct 21, 2017

All real numbers.

#### Explanation:

Hey there!

So I'm not 100% sure on what a 'definition domain' is, but I'm going to assume that you just mean the domain.

For a fraction with polynomials like this, the domain will be all real numbers except when the denominator equals $0$ (since you can't divide by $0$).

So for $\frac{1 + x}{1 + {x}^{2}}$, the domain is all real numbers except when $1 + {x}^{2} = 0$.

Subtracting $1$ from both sides will yield the equation ${x}^{2} = - 1$, which is impossible because any real number squared will be positive.

Hope this helps!