If $$a×b=a+b+ \sqrt{ab}$$   then find the value of 4×9.

Correct option is D

Given:

The operation is defined as: a×b = a + b + √ab

We need to find the value of 4×9.

Solution:

Using the given operation definition:

4×9 = 4 + 9 +$$\sqrt{4\times9}$$​

​$$\sqrt{4\times9}$$​ = = 6

4×9 = 4 + 9 + 6 = 19

The value of 4×9 is 19.