English

If A = {x/6x2 + x – 15 = 0}, B = {x/2x2 – 5x – 3 = 0}, C = {x/2x2 – x – 3 = 0} then find (A ∪ B ∪ C). - Mathematics and Statistics

Advertisements
Advertisements

Question

If A = {x/6x2 + x – 15 = 0}, B = {x/2x2 – 5x – 3 = 0}, C = {x/2x2 – x – 3 = 0} then find (A ∪ B ∪ C).

Sum
Advertisements

Solution

A = {x/6x2 + x – 15 = 0}

∴ 6x2 + x – 15 = 0

∴ 6x2 + 10x – 9x – 15 = 0

∴ 2x(3x + 5) – 3(3x + 5) = 0

∴ (3x + 5) (2x – 3) = 0

∴ 3x + 5 = 0 or 2x – 3 = 0

∴ x = `(-5)/3` or x = `3/2`

∴ A = `{(-5)/3, 3/2}`

B = {x/2x2 – 5x – 3 = 0}

∴ 2x2 – 5x – 3 = 0

∴ 2x2 – 6x + x – 3 = 0

∴ 2x(x – 3) + 1(x – 3) = 0

∴ (x – 3)(2x + 1) = 0

∴ x – 3 = 0 or 2x + 1 = 0

∴ x = 3 or x = `(-1)/2`

∴ B = `{(-1)/2, 3}`

C = {x/2x2 – x – 3 = 0}

∴ 2x2 –  x – 3 = 0

∴ 2x2 – 3x + 2x – 3 = 0

∴ x(2x – 3) + 1(2x – 3) = 0

∴ (2x – 3) + 1(2x – 3) = 0

∴ x(2x – 3) (x + 1) = 0

∴ 2x – 3 = 0 or x + 1 = 0

∴ x = `3/2` or x = – 1

∴ C = `{-1, 3/2}`

A ∪ B ∪ C = `{-5/3,3/2} ∪ {(-1)/2, 3} ∪ {-1, 3/2}`

= `{(-5)/3, -1, (-1)/2, 3/2, 3}`

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Sets and Relations - Exercise 5.1 [Page 97]

APPEARS IN

RELATED QUESTIONS

Identify whether the following is set or not? Justify your answer.

The collection of all natural numbers less than 100.


Write the following set in roster form:

D = {x : x is a prime number which is divisor of 60}


Write the following set in roster form:

F = The set of all letters in the word BETTER


Write the following set in the set-builder form:

{5, 25, 125, 625}


Write the following set in the set-builder form:

{1, 4, 9, ....., 100}


List all the elements of the following set:

A = {x : x is an odd natural number}


List all the elements of the following set:

C = {x : x is an integer, x2 ≤ 4}


List all the elements of the following set:

D = {x : x is a letter in the word “LOYAL”}


List all the elements of the following set:

E = {x : x is a month of a year not having 31 days}


Which of the following collection are sets? Justify your answer: 

 The collection of difficult topics in mathematics.

 


Which of the following collection are sets? Justify your answer: 

 A collection of novels written by Munshi Prem Chand.


If A = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], then insert the appropriate symbol ∈ or ∉ in each of the following blank space: 

4 ...... A  


Describe the following sets in Roster form: 

{x : x is a letter before e in the English alphabet}


Describe the following sets in Roster form: 

{x ∈ N : x2 < 25}; 


Describe the following sets in Roster form: 

{x ∈ N : x is a prime number, 10 < x < 20};


Describe the following sets in Roster form: 

 {x ∈ N : x = 2nn ∈ N};


Describe the following set in Roster form: 

The set of all letters in the word 'Trigonometry'


List all the elements of the following set: 

\[C = \left\{ x: x \text{ is an integer }, - \frac{1}{2} < x < \frac{9}{2} \right\}\]


Write the set of all vowels in the English alphabet which precede q.


Which of the following statements are correct?
Write a correct form of each of the incorrect statement. 

\[a \in {\left\{ a \right\}, b}\]


Let A = {ab, {cd}, e}. Which of the following statements are false and why? 

\[\left\{ a, b, e \right\} \in A\] 


Write down all possible subsets of each of the following set: 

 {a


Let A = {1, 2, 3, 4, 5, 6}. Insert the appropriate symbol ∈ or ∉ in the blank space:

4 _____ A


Describe the following set in Set-Builder form

`{1/2, 2/5, 3/10, 4/17, 5/26, 6/37, 7/50}`


There are 260 persons with skin disorders. If 150 had been exposed to chemical A, 74 to chemical B, and 36 to both chemicals A and B, find the number of persons exposed to Chemical B but not Chemical A


Write the following interval in Set-Builder form

`(6, ∞)`


Answer the following:

Write down the following set in set-builder form

{a, e, i, o, u)


Given that E = {2, 4, 6, 8, 10}. If n represents any member of E, then, write the following sets containing all numbers represented by n + 1


Given that E = {2, 4, 6, 8, 10}. If n represents any member of E, then, write the following sets containing all numbers represented by n2 


Let X = {1, 2, 3, 4, 5, 6}. If n represent any member of X, express the following as sets:
n is greater than 4


Write the following sets in the roaster from:
C = {x | x is a positive factor of a prime number p}


State which of the following statement is true and which is false. Justify your answer.

3 ∉ {x | x4 – 5x3 + 2x2 – 112x + 6 = 0}


Out of 100 students; 15 passed in English, 12 passed in Mathematics, 8 in Science, 6 in English and Mathematics, 7 in Mathematics and Science; 4 in English and Science; 4 in all the three. Find how many passed in English and Mathematics but not in Science.


Out of 100 students; 15 passed in English, 12 passed in Mathematics, 8 in Science, 6 in English and Mathematics, 7 in Mathematics and Science; 4 in English and Science; 4 in all the three. Find how many passed in Mathematics and Science but not in English


In a group of 50 students, the number of students studying French, English, Sanskrit were found to be as follows:
French = 17, English = 13, Sanskrit = 15 French and English = 09, English and Sanskrit = 4 French and Sanskrit = 5, English, French and Sanskrit = 3. Find the number of students who study Sanskrit only


In a group of 50 students, the number of students studying French, English, Sanskrit were found to be as follows:
French = 17, English = 13, Sanskrit = 15 French and English = 09, English and Sanskrit = 4 French and Sanskrit = 5, English, French and Sanskrit = 3. Find the number of students who study at least one of the three languages


Let F1 be the set of parallelograms, F2 the set of rectangles, F3 the set of rhombuses, F4 the set of squares and F5 the set of trapeziums in a plane. Then F1 may be equal to ______.


If sets A and B are defined as A = `{(x, y) | y = 1/x, 0 ≠ x ∈ "R"}` B = {(x, y) | y = – x, x ∈ R}, then ______.


State True or False for the following statement.

Let sets R and T be defined as
R = {x ∈ Z | x is divisible by 2}
T = {x ∈ Z | x is divisible by 6}. Then T ⊂ R


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×