Find the pairs of equal sets, if any, give reasons:\ A = \{0\} B = \{x : x > 15  and x<5\text{ and } x < 5} C = \{x : x - 5 = 0 \} D = \{x: x2=25x^2 = 25} E = \{x : x  is an integral positive root of the equation x2−2x−15=0\text{ is an integral positive root of the equation } x^2 - 2x - 15 = 0}

Answer: The pairs of equal sets are C=EC = E because both sets contain only the element 5.

Step-by-step solution

Step 1: Determine elements of Set A

Set A is explicitly defined as containing only one element, which is 0. No further calculation is needed for this set.

Step 2: Determine elements of Set B

Set B is defined by the condition that xx must be greater than 15 AND less than 5 simultaneously. There is no number that can satisfy both conditions at the same time. Therefore, Set B is an empty set.

Step 3: Determine elements of Set C

Set C is defined by the equation x−5=0x - 5 = 0. Solving this linear equation for xx gives x=5x = 5. Thus, Set C contains only the element 5.

Step 4: Determine elements of Set D

Set D is defined by the equation x2=25x^2 = 25. Taking the square root of both sides yields two possible values for xx: positive 5 and negative 5. Therefore, Set D contains both 5 and -5.

Step 5: Determine elements of Set E

Set E requires finding the integral positive root of the quadratic equation x2−2x−15=0x^2 - 2x - 15 = 0. Factoring the quadratic equation gives (x−5)(x+3)=0(x-5)(x+3) = 0, which means x=5x=5 or x=−3x=-3. Since we are looking for an integral positive root, x=5x=5 is the only valid solution. Thus, Set E contains only the element 5.

Step 6: Identify equal sets

By comparing the elements of all the sets, we find that Set C contains only 5, and Set E also contains only 5. Therefore, Set C and Set E are equal sets.

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