Question

Why is f not a function from R to R if

a) f(x)=1x?


f(x) is not well-defined because there are two distinct values assigned to each x.
f(0) is not defined.
f(x) is not defined for x<0.

Answer 1

Is it \(\large\color{black}{ f(x)=1\times x }\) which is same as \(\large\color{black}{ f(x)=x }\)
OR, is it supposed to be, \(\large\color{blue}{ f(x)=1^x }\) ?