Given, n(A)=3,n(B)=5
⇒n(A×B)=15
x=C35×3!=5×4×3=60
y=C315×3!=15×14×13=30×912y=60×91
∴2y=91x
JEE Main 2021 — Mathematics Algebra
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×B. Then :
Held on 25 Feb 2021 · Verified 6 Jul 2026.
y=273x
2y=273x
2y=91x
y=91x
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