Discover Questions

I am trying to discover a new element. I shall call it Zinc? If m and n are +ve integers then what is limit x -> 1 (x^m-1)/(x^n-1) = ? Can someone help to explain how to do this problem? Like the steps? Find the indicated limit, if it exists.? What is the difference between removable and a non-removable discontinuity? In the ionic compound with the general formula M2X3, the likely charge on X is? Please explain.?