I have a clarification to make with my notes. This is about functions. It defines the function
$$f(x) = \sqrt[5]{x+1} \space\text{from} \space x=(-1,\infty) \space \text{to} \space[0,\infty)$$
And it defines the inverse as
$$f^{-1}(x) = x^5 - 1 \space\text{from} \space x=[0,\infty) \space \text{to} \space(-1,\infty)$$
I have some questions:
Shouldn't the range of $f$ be $(0,\infty) $ instead of $[0,\infty) $? Either we change that or we say
$$f(x) \space \text{is from}\space x=[-1,\infty) \space \text{to} \space[0,\infty)\\ \text{and} \\ f^{-1}(x) \space \text{is from}\space x=[0,\infty) \space \text{to} \space[-1,\infty) $$
Please help.
UPDATE: Thank you for your help. I think there are 2 ways to do this: either the one above or:
$$f(x) \space \text{is from}\space x=(-1,\infty) \space \text{to} \space(0,\infty)\\ \text{and} \\ f^{-1}(x) \space \text{is from}\space x=(0,\infty) \space \text{to} \space(-1,\infty) $$
We always know that if $f:X\to Y$ be a one-one and onto and so its inverse exists; then : $$D_f=R_{f^{-1}}=X$$ and $$D_{f^{-1}}=R_f=Y$$
I have a counterexample to the above statement. The function $$y=x^{3}-1$$ is 1-1 and onto. Its domain and range are set of all real numbers. But its inverse $$y=(x+1)^{1/3}$$ has domain $$[-1,\infty)$$ and range $$[0,\infty).$$ How would you see your conclusion in this situation?