Are the following pairs of sets equal? Give reasons.
(i) A = {2, 3} and B = {x : x is solution of x2+5x+6=0}
(ii) A = {x : x is a letter in the word FOLLOW}
B = { y : y is a letter in the word WOLF}
(i) A = {2, 3} and
B = {x : x is solution of x2+5x+6=0}
Now x2+5x+6=0
⇒ x2+3x+2x+6=0
⇒ (x+3) (x+2)=0 ⇒ x=−3, −2
∴ B={−2, −3}
Hence A and B are not equal sets.
(ii) A = {x : x is a letter in the word FOLLOW}
= {F, O, L, W}
B = {y : y is a letter in the word WOLF} = {W, O, L, F}
Hence A = B = {F, O, L, W}