Question

If `f(x) = sqrt(x-10)` and `g(x) = -x`, what is `f+g` and its domain?

Answer 1

`f(x)=sqrt(x-10)`, `g(x)=-x`, so
`f+g(x)=sqrt(x-10)-x`

The domain would be `x in [10, ∞)` because `sqrt0` is possible, but `sqrt(-1)` is a math error (you can look into that if you're interested, `sqrt(-1)` is termed `i`, stands for imaginary unit)