Q: The term independent of x in $\large (\sqrt{\frac{x}{3}} + \sqrt{\frac{3}{2x^2}} )^{10} $ is
(A) 1
(B) 5/12
(C) 10C1
(D) None of these
Sol. General term in the expansion is
$\large = 10_{C_r} (\frac{x}{3})^{r/2} (\frac{3}{2x^2})^{\frac{10-r}{2}}$
$\large = 10_{C_r} x^{\frac{3r}{2}-10} . \frac{3^{5-r}}{2^{(10-r)/2}}$
For constant term, 3r/2 = 10 ⇒ r = 20/3
which is not an integer. Therefore, there will be no constant term.
Hence (D) is the correct answer.