The number of surjection from \[A=\{1,2,...,n\},n\ge 2ontoB=\{a,b\}\] is

The number of surjection from \[A=\{1,2,...,n\},n\ge 2ontoB=\{a,b\}\]

1.	The number of surjection from \[A=\{1,2,...,n\},n\ge 2ontoB=\{a,b\}\] is
A.	\[^{n}{{P}_{2}}\]
B.	\[{{2}^{n}}-2\]
C.	\[{{2}^{n}}-1\]
D.	None of these
Answer» C. \[{{2}^{n}}-1\]

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The number of surjection from \[A=\{1,2,...,n\},n\ge 2ontoB=\{a,b\}\] is

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