Maths-

General

Easy

Question

# The number of one one onto functions that can be defined from A={a,b,c,d} into B={1,2,3,4} is

- 12
- 24
- 18
- 26

Hint:

### Use the cardinality of two sets to find the number of one-one functions between them.

## The correct answer is: 24

### STEP BY STEP SOLUTION

Number of one-one functions =

Number of one-one functions = 0 if

As we know the given set A & B is

A = and B =

Here cardinality of A =

Cardinality of B =

Number of one-one functions =

We can see that n=m

So, the number of one-one functions =

By using the formula,

The total number of one-one functions = 24

### Related Questions to study

maths-

### The number of ways one can arrange words with the letters of the word ’ so that ↑MADHURI↑ always vowels occupy the beginning, middle and end places is

### The number of ways one can arrange words with the letters of the word ’ so that ↑MADHURI↑ always vowels occupy the beginning, middle and end places is

maths-General

Maths-

### If defined by

### If defined by

Maths-General

physics

### An ant goes from P to Q on a circular path in 20 second Radius OP=10 m . What is the average speed and average velocity of it ?

### An ant goes from P to Q on a circular path in 20 second Radius OP=10 m . What is the average speed and average velocity of it ?

physicsGeneral

Maths-

Which of the following functions is not injective?

Which of the following functions is not injective?

Maths-General

physics

### The graph of position time shown in the figure for a particle is not possible because ....

### The graph of position time shown in the figure for a particle is not possible because ....

physicsGeneral

physics-

### Curie-Weiss law is obeyed by iron

### Curie-Weiss law is obeyed by iron

physics-General

physics-

### If the curves of two samples of P and Q of iron are as shown below, then which one of the following statements is correct?

### If the curves of two samples of P and Q of iron are as shown below, then which one of the following statements is correct?

physics-General

physics-

### Among the following properties describing diamagnetism identify the property that is wrongly stated

### Among the following properties describing diamagnetism identify the property that is wrongly stated

physics-General

physics-

### Permanent magnet has properties retentivity and coercivity respectively

### Permanent magnet has properties retentivity and coercivity respectively

physics-General

physics-

### The magnetic susceptibility of a paramagnetic substance at C is 0.0060, then its value atC will be

### The magnetic susceptibility of a paramagnetic substance at C is 0.0060, then its value atC will be

physics-General

physics-

### If a magnetic substance is kept in a magnetic field then which of the following substance is thrown out?

### If a magnetic substance is kept in a magnetic field then which of the following substance is thrown out?

physics-General

physics-

### Curie temperature is the one above which

### Curie temperature is the one above which

physics-General

physics-

### Which of the following is represented by the area enclosed by a hysteresis loop (B-H curve)?

### Which of the following is represented by the area enclosed by a hysteresis loop (B-H curve)?

physics-General

physics-

### For a paramagnetic material, the dependence of the magnetic susceptibility X on the absolute temperature is given as

### For a paramagnetic material, the dependence of the magnetic susceptibility X on the absolute temperature is given as

physics-General

physics-

### Susceptibility of ferromagnetic substance is

### Susceptibility of ferromagnetic substance is

physics-General