4 ms·0^-1 is definitely infinity x^(-1) doesn't have an upper bound as x approaches zero.by rorrr 15y ago0^-1 is definitely infinity x^(-1) doesn't have an upper bound as x approaches zero.kbutler 15y agoTry approaching 0 from both the positive and negative sides.rorrr 15y agoSo you get a +∞ or -∞.kbutler 15y agoBut what's 0^-1? grin