Let f(x)=\frac{x-1}{x^{2}} then which of the following is correct?

{f}( {x}) has minima but no maxima.

f(x) increases in the interval (0,2) and decreases in the interval (-\infty, 0) \cup(2, \infty).

f(x) is concave down in (-\infty, 0) \cup(0,3)