Browse by Stream
QnA
Home
Search for Exam, Articles, Questions
QnA
get app
Go To Your Study Dashboard
  1. Home
  2. Engineering
  3. Find the number of onto functions from A to B where n(A) = 5 and n(B) = 3
# Engineering

Number of onto functions from A to B = n(A)Cn(B) = 5C3 = 10

Answers (1)
L Lovekush Kumar Saini

As we have learned

Number of Onto function -

f:A\rightarrow B

Such\: that\: n\left ( A \right )= m

&                    n\left ( B\right )=n

m\geqslant n

Number of onto functions = \sum_{r=1}^{n}\left ( -1 \right )^{n-r}n_{C_{r}}r^{m}

-

 

 \sum_{r=1}^3{}(-1)^{3-r} C_{r}^{3}\textrm{} * {r^{5}}

\Rightarrow C_{1}^{3}\textrm{}- C_{2}^{3}\textrm{}* 2^5+ C_{3}^{3}\textrm{}*3^5

\Rightarrow 3-96+243\Rightarrow 243-93

= 150

Similar Questions

Latest Asked Questions

Most Viewed Questions

Preparation Products

JEE Foundation + Knockout JEE Main 2025 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-
Buy Now
JEE Foundation + Knockout JEE Main 2024 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-
Buy Now
Knockout JEE Main April 2021 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 14000/- ₹ 4999/-
Buy Now
Knockout JEE Main May 2021

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 22999/- ₹ 9999/-
Buy Now
Knockout BITSAT 2021

It is an exhaustive preparation module made exclusively for cracking BITSAT..

₹ 4999/- ₹ 2999/-
Buy Now
Boost your Preparation for JEE Main 2021 with Personlized Coaching
Start Now
 
Exams
Articles
Questions