Question

formula of number of nodes in any orbital is equal to n minus l minus 1 what is the meaning of nodes here .....​

Answer 1

nodes:- region or space around the nucleus where probability of finding the electron is zero..

Answer 2

This means there there must be two radial nodes. The number of radial and angular nodes can only be calculated if the principal quantum number, type of orbital (s,p,d,f), and the plane that the orbital is resting on (x,y,z, xy, etc.) are known.