what is || in math?

Answer 1

eleven or two parallel lines

Answer 2

It really has 2 meanings:
1). Is parallel to(as pointed out above).
A||B means line A is parallel to line B.

2). Exactly divides. If a and b are integers,
a|b means a divides b, i.e., a goes into b without
remainder.
Now let p be a prime divisor of b.
We write p^n||b if p^n divides b but no higher
power of p divides b.
Example: 3³||27 because 3³ | 27 but 3^4 doesn't
divide 27.

Answer 3

It *can* refer to the absolute value function. For example,

f(x) = |x|

The absolute value function is defined to be

|x| = { x, if x >= 0
{ -x, if x < 0

Basically, it accepts a number and always spits out a positive number. |5| = 5, |-3| = 3.

But it depends which concept you speak of || in.

Answer 4

it means parallel

Answer 5

it means parallel