x > 0 | means: x is larger than '0' |
x ≥ 0 | means: x is larger or equal to '0' |
x < 0 | means: x is smaller than '0' |
x ≥ 0 | means: x is larger or equal to '0' |
x ≤ 0 | means: x is smaller or equal to '0' |
-5 < x < 5 | means: x is smaller than '5', but larger than '-5' |
a ∧ b | means: a AND b |
a ∨ b | means: a OR b |
∀ x | means: for all x (in some set) |
∃ x | means: there exists some x (in some set) |
x1= | -b + √(b2 -4ac) -------------------               2a |
x2= | -b - √(b2 -4ac) -------------------               2a |