Let X=R . Define a relation R on X as : (a1,b1)R(a2,b2) b1=b2 In the light of the above statements, choose the correct answer from the options given below :
- Both Statement I and Statement II are true
- Statement I is true but Statement II is false
- Both Statement I and Statement II are false
- Statement I is false but Statement II is true
Answer
(2) Statement I is true but Statement II is false
Solution
R, "same second coordinate", is reflexive (b1=b1), symmetric and transitive (equality of b) equivalence relation: Statement I true.
[figure]
Related points of (a,b) are all (x,y) with y=b: the horizontal line y=b (slope 0), never parallel to y=x (slope 1).
Statement II false.
Answer: (2)