Are the following pair of sets equal? Give reasons.
A = {2, 3}; B = {x : x is solution of x² + 5x + 6 = 0}
No, A and B are not equal sets. A = {2, 3} and B = {-2, -3}. The elements of A are different from elements of B.
A = {x : x is a letter in the word FOLLOW}; B = {y : y is a letter in the word WOLF}
Yes, A and B are equal sets. A = {F, O, L, W} and B = {W, O, L, F}. Both sets have exactly the same elements.
Explanation
For part (i), students need to solve the quadratic equation x² + 5x + 6 = 0 by factorization to find B = {-2, -3}. Since A contains positive integers 2 and 3, while B contains negative integers -2 and -3, the sets are not equal. For part (ii), the context clearly states that 'repetition of elements in a set do not change a set' and sets are equal if 'they have exactly the same elements.' Both words contain the same unique letters F, O, L, W, making the sets equal.