Equivalent to 。

Equivalence is a mathematical formula. As mentioned above, funds have time value, even if the amount is the same, because their value is different at different times. On the contrary, absolutely unequal funds may be of equal value at different time points under the action of time value.

These funds with different maturities and different amounts but "equivalent" are called equivalence, also called equivalence. Capital equivalence and compound interest are calculated in the same form.

Concept definition:

Let a and b be two propositional formulas. If the equivalent formulas A and B are tautologies, then A and B are said to be equivalent, which is denoted as A.

The truth table method can judge whether two propositional formulas are equivalent according to the definition, but the truth table can be simplified. Let A and B be two propositional formulas, and judge whether A and B are equivalent by definition.

Many equivalent formulas are verified by truth table method, and some of them are very important and are an important part of Boolean algebra. The important equivalent formula is one of the keys to learn mathematical logic well.

The contour map can reflect the altitude, temperature difference and gentle fluctuation of an area. There are several types of isolines, such as isolines, isotherms and isobars. Pay attention to the density of isolines and the difference between isolines when reading. Many conclusions can be drawn from the distribution of isoline.