examday

/TMUA

The expansion of the expression $\left(x^p+\dfrac{1}{x^q}\right)^n$ has a constant term.

Which of the following is/are necessary and sufficient conditions for this statement for some integer $k$?

• I: $kp+kq=n$
• II: $kp+kq=nq$
• III: $kp+kq=np$