Let x denote total number of one-one functions from a set A with 3 elements to a set B with 5 e

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1.Relation and Function

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Let $x$ denote the total number of one-one functions from a set $A$ with $3$ elements to a set $B$ with $5$ elements and $y$ denote the total number of one-one functions from the set $A$ to the set $A \times B$. Then ...... .

A

$y=273 x$

B

$2 y=91 x$

C

$y=91 x$

D

$2 y=273 x$

(JEE MAIN-2021)

Solution

$x={ }^{5} C_{3} \times 3 !=60$

$y={ }^{15} C_{3} \times 3 !=15 \times 14 \times 13=30 \times 91$

$\therefore 2 y=91 x$

Standard 12

Mathematics

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