Question

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Explanation:

Step1: Find $B^c$ (complement of B)

$B^c = S - B = \{1,2,4,6,8,9,12,13,16,17,18\}$

Step2: Compute $A \cap B^c$

$A \cap B^c = \{1,2,3,4,5,7,8,11,16,18\} \cap \{1,2,4,6,8,9,12,13,16,17,18\}$

Step3: Find $A^c$ (complement of A)

$A^c = S - A = \{6,9,10,12,13,14,15,17,19,20\}$

Step4: Compute $B \cap A^c$

$B \cap A^c = \{3,5,7,10,11,14,15,19,20\} \cap \{6,9,10,12,13,14,15,17,19,20\}$

Answer:

$(A \cap B^c) = \{1,2,4,8,16,18\}$
$(B \cap A^c) = \{10,14,15,19,20\}$