Consider the following relations from A to B where A = {u, v, w, x, y, z} and B = {p, q, r, s}. 1. {(u, p}, (v, p), (w, p), (x, q), (y, q), (z, q)} 2. {(u, p), (v, q), (w, r), (z, s)} 3. {(u, s), (v, r), (w, q), (u, p), (v, q), (z, q)} 4. {(u, q), (v, p), (w, s), (x, r), (y, q), (z, s)} Which of the above relations are not functions?
Consider the following relations from A to B where A = {u, v, w, x, y, z} and B = {p, q, r, s}. 1. {(u, p}, (v, p), (w, p), (x, q), (y, q), (z, q)} 2. {(u, p), (v, q), (w, r), (z, s)} 3. {(u, s), (v, r), (w, q), (u, p), (v, q), (z, q)} 4. {(u, q), (v, p), (w, s), (x, r), (y, q), (z, s)} Which of the above relations are not functions? Correct Answer 2 and 3
Concept:
A relation from a set X to a set Y is called a function if
- Each element in the set X has its image in set Y.
- It is also possible that these are few elements in set y which are not the image of any element in set X.
- Every element in set X should have one and only one image.
Calculation:
Given that, A = {u, v, x, y, z); B = {p, q, r, s}
As we know, a mapping f: x + y is said to be a function,
1. [ alt="F1 Aman.k 26-08-2020 Savita D5" src="//storage.googleapis.com/tb-img/production/20/08/F1_Aman.k_26-08-2020_Savita_D5.png" style="width: 182px; height: 173px;">
Its a function
2. [ alt="F1 Aman.k 26-08-2020 Savita D6" src="//storage.googleapis.com/tb-img/production/20/08/F1_Aman.k_26-08-2020_Savita_D6.png" style="width: 182px; height: 173px;">
Here, each elements in A has not its image in B, so its not a function
3. [ alt="F1 Aman.k 26-08-2020 Savita D7" src="//storage.googleapis.com/tb-img/production/20/08/F1_Aman.k_26-08-2020_Savita_D7.png" style="width: 182px; height: 173px;">
Here, each elements in A has not its image in B, so its also not a function
4. [ alt="F1 Aman.k 26-08-2020 Savita D8" src="//storage.googleapis.com/tb-img/production/20/08/F1_Aman.k_26-08-2020_Savita_D8.png" style="width: 182px; height: 173px;">
Its a function
Hence, option (3) is correct.