Which of the following pairs of sets are equal? Justify your answer. (i) X, the set of letters in “ALLOY” and B, the set of letters in “LOYAL”. (ii) A = \{n : n ∈Z and n2=4\in Z\text{ and } n^2 = 4} and B = \{x : x ∈R and x2−3x+2=0\in R\text{ and } x^2 - 3x + 2 = 0}.

Answer: (i) The sets X and B are equal. (ii) The sets A and B are not equal.

Step-by-step solution

Step 1: Determine the elements of set X and set B for part (i)

To determine if two sets are equal, we first need to list all the distinct elements in each set. For part (i), set X consists of the unique letters in the word "ALLOY", and set B consists of the unique letters in the word "LOYAL". We extract each unique letter to form the sets.

Step 2: Compare set X and set B for part (i)

Two sets are considered equal if they contain exactly the same elements, regardless of the order in which the elements are listed. Since both set X and set B contain the same four letters (A, L, O, Y), they are equal.

Step 3: Determine the elements of set A for part (ii)

For part (ii), set A is defined as all integers nn such that n2=4n^2 = 4. We solve this equation to find the possible integer values for nn. The solutions are n=2n = 2 and n=−2n = -2. Both of these are integers, so they are included in set A.

Step 4: Determine the elements of set B for part (ii)

Set B is defined as all real numbers xx such that x2−3x+2=0x^2 - 3x + 2 = 0. We solve this quadratic equation by factoring. The factors are (x−1)(x-1) and (x−2)(x-2), which gives us the solutions x=1x=1 and x=2x=2. Both of these are real numbers, so they are included in set B.

Step 5: Compare set A and set B for part (ii)

Now we compare the elements of set A and set B. Set A contains {−2,2}\{-2, 2\} and set B contains {1,2}\{1, 2\}. Since set A contains −2-2 but not 11, and set B contains 11 but not −2-2, the two sets do not contain exactly the same elements. Therefore, set A and set B are not equal.

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