Question

If `2^(x + y) = 2^(x - y) = sqrt(8)` then the value of y is ______.

पर्याय

• `1/2`

• `3/2`

• 0

• none of these

Answer 1

If `2^(x + y) = 2^(x - y) = sqrt(8)` then the value of y is 0.

Explanation:

`sqrt(8) = 2^(3/2)`, so `2^(x + y) = 2^(3/2)` and `2^(x - y) = 2^(3/2)`. 

Thus, `x + y = 3/2` and `x - y = 3/2`. 

Subtract the second from the first:

2y = 0

⇒ y = 0