Question

In the expansion of ${(\sqrt{2}+\sqrt[5]{53})}^{120}$ the number of irrational terms is

• A. $12$
• B. $13$
• C. $108$
• D. $54$

Answer 1

Answer: (C)

$108$

Total number of rational terms is
$\frac{120}{L.C.M(5,2)}+1$
$=\frac{120}{10}+1$
$=13$
Hence total number of irrational terms are
$=121-13$
$=108$