English

If the Binary Operation ⊙ is Defined on the Set Q+ of All Positive Rational Numbers by a ⊙ B = a B 4 . Then , 3 ⊙ ( 1 5 ⊙ 1 2 ) is Equal to - Mathematics

Advertisements
Advertisements

Question

If the binary operation ⊙ is defined on the set Q+ of all positive rational numbers by \[a \odot b = \frac{ab}{4} . \text{ Then }, 3 \odot \left( \frac{1}{5} \odot \frac{1}{2} \right)\] is equal to __________ .

Options

  • `3/160`

  • `5/160`

  • `3/10`

  • `3/40`

MCQ

Solution

`3/160`

Given : \[a \odot b = \frac{ab}{4}\]

\[3 \odot \left( \frac{1}{5} \odot \frac{1}{2} \right) = 3 \odot \left[ \frac{\left( \frac{1}{5} \right)\left( \frac{1}{2} \right)}{4} \right]\]
\[ = 3 \odot \left( \frac{1}{40} \right)\]
\[ = \frac{3\left( \frac{1}{40} \right)}{4}\]
\[ = \frac{3}{160}\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 3: Binary Operations - Exercise 3.7 [Page 37]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 3 Binary Operations
Exercise 3.7 | Q 10 | Page 37

RELATED QUESTIONS

Determine whether or not each of the definition of given below gives a binary operation. In the event that * is not a binary operation, give justification for this.

On R, define * by ab2


Determine whether or not each of the definition of given below gives a binary operation. In the event that * is not a binary operation, give justification for this.

On Z+, define * by = |− b|


For each binary operation * defined below, determine whether * is commutative or associative.

On Q, define ab + 1


Let*′ be the binary operation on the set {1, 2, 3, 4, 5} defined by *′ = H.C.F. of and b. Is the operation *′ same as the operation * defined in Exercise 4 above? Justify your answer.


Number of binary operations on the set {ab} are

(A) 10

(B) 16

(C) 20

(D) 8


Determine whether the following operation define a binary operation on the given set or not :

\[' +_6 ' \text{on S} = \left\{ 0, 1, 2, 3, 4, 5 \right\} \text{defined by}\] 
\[a +_6 b = \begin{cases}a + b & ,\text{ if a} + b < 6 \\ a + b - 6 & , \text{if a} + b \geq 6\end{cases}\]


Determine whether or not the definition of * given below gives a binary operation. In the event that * is not a binary operation give justification of this.
On Z+, defined * by a * b = a − b

Here, Z+ denotes the set of all non-negative integers.


Determine whether or not the definition of *given below gives a binary operation. In the event that * is not a binary operation give justification of this.

On Z+, defined * by a * b = ab

Here, Z+ denotes the set of all non-negative integers.


Let S = {abc}. Find the total number of binary operations on S.


Check the commutativity and associativity of the following binary operations '⊙' on Q defined by a ⊙ b = a2 + b2 for all a, b ∈ Q ?


On Z, the set of all integers, a binary operation * is defined by a * b = a + 3b − 4. Prove that * is neither commutative nor associative on Z.


Let S be the set of all rational numbers except 1 and * be defined on S by a * b = a + b \[-\] ab, for all a, b \[\in\] S:

Prove that * is commutative as well as associative ?


Let * be a binary operation on Z defined by
a * b = a + b − 4 for all a, b ∈ Z Find the identity element in Z ?


Let * be a binary operation on Q − {−1} defined by a * b = a + b + ab for all a, b ∈ Q − {−1} Show that '*' is both commutative and associative on Q − {−1}.


Let A = R0 × R, where R0 denote the set of all non-zero real numbers. A binary operation '⊙' is defined on A as follows (ab) ⊙ (cd) = (acbc + d) for all (ab), (cd) ∈ R0 × R :

Find the identity element in A ?

 


Let A = R0 × R, where R0 denote the set of all non-zero real numbers. A binary operation '⊙' is defined on A as follows (a, b) ⊙ (c, d) = (ac, bc + d) for all (a, b), (c, d) ∈ R0 × R :

Find the invertible elements in A ?


Let 'o' be a binary operation on the set Q0 of all non-zero rational numbers defined by \[a o b = \frac{ab}{2}, \text{ for all a, b } \in Q_0\] :

 Find the identity element in Q0.


Let R0 denote the set of all non-zero real numbers and let A = R0 × R0. If '*' is a binary operation on A defined by

(a, b) * (c, d) = (ac, bd) for all (a, b), (c, d) ∈ A

Find the identity element in A ?


Construct the composition table for ×6 on set S = {0, 1, 2, 3, 4, 5}.


Find the inverse of 5 under multiplication modulo 11 on Z11.


Define a binary operation on a set.


Let * be a binary operation, on the set of all non-zero real numbers, given by \[a * b = \frac{ab}{5} \text { for all a, b } \in R - \left\{ 0 \right\}\]

Write the value of x given by 2 * (x * 5) = 10.


Define identity element for a binary operation defined on a set.


Write the composition table for the binary operation multiplication modulo 10 (×10) on the set S = {2, 4, 6, 8}.


For the binary operation multiplication modulo 5 (×5) defined on the set S = {1, 2, 3, 4}. Write the value of \[\left( 3 \times_5 4^{- 1} \right)^{- 1}.\] 


A binary operation * is defined on the set R of all real numbers by the rule \[a * b = \sqrt{  a^2 + b^2} \text{for all a, b } \in R .\]

Write the identity element for * on R.


Let * be a binary operation on set of integers I, defined by a * b = 2a + b − 3. Find the value of 3 * 4.


If a * b = a2 + b2, then the value of (4 * 5) * 3 is _____________ .


Which of the following is true ?


Subtraction of integers is ___________________ .


On Z an operation * is defined by a * b = a2 + b2 for all a, b ∈ Z. The operation * on Z is _______________ .


For the multiplication of matrices as a binary operation on the set of all matrices of the form \[\begin{bmatrix}a & b \\ - b & a\end{bmatrix}\] a, b ∈ R the inverse of \[\begin{bmatrix}2 & 3 \\ - 3 & 2\end{bmatrix}\] is ___________________ .


On Z, define * by (m * n) = mn + nm : ∀m, n ∈ Z Is * binary on Z?


Let A = `((1, 0, 1, 0),(0, 1, 0, 1),(1, 0, 0, 1))`, B = `((0, 1, 0, 1),(1, 0, 1, 0),(1, 0, 0, 1))`, C = `((1, 1, 0, 1),(0, 1, 1, 0),(1, 1, 1, 1))` be any three boolean matrices of the same type. Find A v B


Let * be the binary operation on N given by a * b = HCF (a, b) where, a, b ∈ N. Find the value of 22 * 4.


Which of the following is not a binary operation on the indicated set?


Determine which of the following binary operation on the Set N are associate and commutaive both.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×