Middle term (√x+√y) ^8

There is 9 terms in the expansion so the middle term is the 5th.

(r + 1) th term of (a + b) ^n = nCr a^ (n-r) b^r

So here 5th term = (4 + 1) th term

= 8C4 (x^1/2) ^ (8-4) (y^1/2) ^4

= 70 x^2 y^2 answer