isi-entrance 2010 Q20

isi-entrance · India · solved Number Theory Properties of Integer Sequences and Digit Analysis

The digit at the unit place of $$(1! - 2! + 3! - \ldots + 25!)^{(1! - 2! + 3! - \ldots + 25!)}$$ is
(a) 0
(b) 1
(c) 5
(d) 9

The digit at the unit place of
$$(1! - 2! + 3! - \ldots + 25!)^{(1! - 2! + 3! - \ldots + 25!)}$$
is\\
(a) 0\\
(b) 1\\
(c) 5\\
(d) 9