Question

IF x+ y= 12, the maximum value of the product of xy is

(a) 26 (b) 36

(c) 30 (d) None of these

Answer 1

b) 36 because if x=y then x = 6

Another way to find

Factors of:-

26:- 1,2,13,26
30:- 1,2,3,5,6,10,15,30
36:- 1,2,3,4,6,9,12,18,36

The factors of 24 can't be used to form 12

Factors of 30 can be formed{10+2}. Product = 20

Factors of 36 can be formed{9+3}. Product = 27

But according to options, it doesn't satisfied.

But there is still a number, 6+6, which is 12. 6²= 36