The sum of the series $$\frac{1}{1+\sqrt{2}} + \frac{1}{\sqrt{2}+\sqrt{3}} + \frac{1}{\sqrt{3}+\sqrt{4}} + \ldots$$ upto 15 terms is (1) 1 (2) 2 (3) 3 (4) 4
The sum of the series
$$\frac{1}{1+\sqrt{2}} + \frac{1}{\sqrt{2}+\sqrt{3}} + \frac{1}{\sqrt{3}+\sqrt{4}} + \ldots$$
upto 15 terms is\\
(1) 1\\
(2) 2\\
(3) 3\\
(4) 4