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Given A={x:x is a root of x^(2)-1=0},B={...

Given A={x:x is a root of `x^(2)-1=0`},B={x:x is a root of `x^(2)-2x+1=0`} then (a)`AnnB=B`(b)`AnnB=A`(c) `AuuB=A`(d)`AnnB=phi`

A

`AnnB=B`

B

`AnnB=A`

C

`AuuB=A`

D

`AnnB=phi`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to evaluate the sets A and B based on the roots of the equations provided, and then determine the relationships between these sets. ### Step 1: Determine the set A Set A is defined as the set of roots of the equation \(x^2 - 1 = 0\). 1. Solve the equation: \[ x^2 - 1 = 0 \implies x^2 = 1 \implies x = \pm 1 \] 2. Therefore, the set A is: \[ A = \{1, -1\} \] ### Step 2: Determine the set B Set B is defined as the set of roots of the equation \(x^2 - 2x + 1 = 0\). 1. Solve the equation: \[ x^2 - 2x + 1 = 0 \implies (x - 1)^2 = 0 \implies x - 1 = 0 \implies x = 1 \] 2. Therefore, the set B is: \[ B = \{1\} \] ### Step 3: Evaluate the intersection of A and B Now we need to find the intersection of sets A and B, denoted as \(A \cap B\). 1. The intersection consists of elements that are common to both sets: \[ A \cap B = \{1, -1\} \cap \{1\} = \{1\} \] ### Step 4: Evaluate the union of A and B Next, we evaluate the union of sets A and B, denoted as \(A \cup B\). 1. The union consists of all elements that are in either set: \[ A \cup B = \{1, -1\} \cup \{1\} = \{1, -1\} \] ### Step 5: Analyze the options Now we can analyze the options provided in the question: (a) \(A \cap B = B\) - We found \(A \cap B = \{1\}\) and \(B = \{1\}\), so this is **true**. (b) \(A \cap B = A\) - We found \(A \cap B = \{1\}\) and \(A = \{1, -1\}\), so this is **false**. (c) \(A \cup B = A\) - We found \(A \cup B = \{1, -1\}\) and \(A = \{1, -1\}\), so this is **true**. (d) \(A \cap B = \phi\) - We found \(A \cap B = \{1\}\), so this is **false**. ### Conclusion The correct options are: - (a) \(A \cap B = B\) is true. - (c) \(A \cup B = A\) is true.
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ML KHANNA-CONCEPTS OF SET THEORY -Problem Set (1)
  1. Let n(U)=700, n(A)=200,n(B)=300 and n(AnnB)=100, then find n(A'nnB')

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  2. In a group of 1000 people, there are 750 who can speak Hindi and 400 w...

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  3. Of the members of three athletic teams in a certain school, 21 are in ...

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  4. An investigator interviewed 100 students to determine their preference...

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  5. In a survey of 200 students of a school, it was found that 120 study...

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  6. A survey shows that 63% of the Indians like cheese, whereas 76% like a...

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  7. In a pollution study of 1500 Indian rivers the following data were rep...

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  8. A group of 123 workers went to a canteen for cold drinks, ice-cream an...

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  9. A survey of 500 television watchers produced the following information...

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  10. In a town of 10,000 families it was found that 40% families buy newspa...

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  11. In a town of 10,000 families it was found that 40% families buy newspa...

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  12. In a town of 10,000 families it was found that 40% families buy newspa...

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  13. The report of one survey of 100 students stated that the numbers study...

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  14. A survey conducted on 600 students of B.A. part I classes of a college...

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  15. Let A, B, C be subsets of the universal set U. If n(U)=692,n(B)=230,</...

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  16. If the set A contains 5 elements, then the number of elements in the p...

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  17. Given A={x:x is a root of x^(2)-1=0},B={x:x is a root of x^(2)-2x+1=0}...

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  18. Let S = {1,2,3,4}. The total number of unordered pairs of disjoint sub...

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  19. 25 people for programme A, 50 people for programme B, 10 people for bo...

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  20. Let X""=""{1,""2,""3,""4,""5} . The number of different ordered pairs ...

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