JEE Main202622 January 2026Morning ShiftMathematicsSets and RelationsActual
Let the relation R on the set M = 1,2,3, , 16 be given by R = (x, y): 4 y=5 x-3, x, y M . Then the minimum number of elements required to be added in R, in order to make the relation symmetric, is equal to
Options
- A4
- B1
- C2
- D3
Correct answer
C. 2
Step-by-step solution
Given R = (x, y) : 4y = 5x - 3, x, y M where M = 1, 2, , 16 . From 4y = 5x - 3 , we get y = 5x-3 4 . For y to be a positive integer, 5x - 3 0 4 , i.e., x 3 4 . So x = 3, 7, 11, 15 . x=3 y=3 , x=7 y=8 , x=11 y=13 , x=15 y=18 M . R = (3,3), (7,8), (11,13) . For symmetry, (7,8) R requires (8,7) R and (11,13) R requires (13,11) R . (3,3) is already symmetric. Minimum elements to be added = 2 .