If `tan px = cot qx,` then the solutions are in A.P. with common difference

If tan p theta = cot q theta and p ne -q show that the solution are in A.P with common difference (pi)/(p+q)

If tanptheta= cotqtheta and pneq show that the solutions are in A.P with common difference (pi)/(p+q)

Solutions of sec qx+sec px=0 form AP with common difference

The 11th term of an A.P. is 60 less than the 31st term of an A.P. . Find the common difference.

The first and last term of an A.P. are a and l respectively. If S be the sum of all the terms of the A.P., them the common difference is