Question

Find the value of sgn (-1) + sgn (1) + sgn (5) + sgn (0), where sgn is the signum function.
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Answer 1

Signum function gives the sign of a number.

-1 for negative numbers, zero for zero and +1 for positive numbers.

$\Rightarrow$ sgn (-1)= -1

Sgn (1)= 1

Sgn (5)= 1

Sgn(0)= 0

$\Rightarrow$ sum= -1 + 1 + 1 + 0

= 1