MATLAB: Figuring out the index of a vector which matches certain criterion

Question

say i have a vector x1 = [3,4,6,7,8,9]; say i have another vector x2 = [4,8];

is there a way to figure out the index where x2 has occured inside x1. That is the solution i want is another vector x3 = [2,5], 2 and 5 being the respective index where x2(1) and x2(2) has occured inside vector x1.

Answer 1

The ismember command