Be equal to, be proportional to

≯, not less than

≯ Not greater than

∧ Logical conjunction statement A ∧ B is true, if both A and B are true; Otherwise it's fake. n & lt4∧n & gt； 2 ? When n is a natural number, N = 3.

Mathematical symbols are also called outer products. The original determinant of a∧b=a 1b2-b 1a2.

∨ Logical disjunction statement A ∨ B is true, if A or B (or both) is true; If both are false, the statement is false. n ≥ 4 ∨ n ≤ 2？ N ≠ 3 When n is a natural number.

It is involved in this book, but it is probably an internal product symbol.