The quantity of the opposite meaning, the quantity of the opposite meaning, who gave me an example

Quantities of opposite meaning are two numbers with opposite signs, representing different positions relative to the datum point (0 point), and it does not matter whether their absolute values are equal or not.

The opposite number is the opposite of the positive and negative signs, and the absolute value must also be the same quantity.

When it comes to the numbers you are talking about, +5 and -4 are quantities in opposite senses, but they are not opposites.

5 and -5 are both quantities and numbers of opposite meanings.

For example, if you have an east-west road, it is positive to go east and negative to go west.

Two cars, starting from point A, driving at both ends respectively, car 1 went 10 kilometers east, which is denoted as +10; Car 2 travels 10 kilometers west and is denoted as -10

In real life, there are various kinds of quantities, and there is a quantity that has the same property but has the opposite meaning, and we call such a quantity a quantity with the opposite meaning. For example, the income is 25 yuan, and the expenditure is 7 yuan; 678 km above sea level and 33 km below sea level; Wait a minute. Take temperature, for example:

One day, the thermometer showed a temperature of minus 13 degrees Celsius in the morning and minus 3 degrees Celsius in the evening. (Above and below zero are based on 0 degrees Celsius).

An quantity with opposite meaning must meet two conditions:

1: They are quantities of the same property.

For example, if you have risen 9 meters and moved 7 meters to the east, you will have a different way of moving, so they are not the same property.

2: They have opposite meanings.

For example, income and expenditure, above and below zero, east and west, deposit and expenditure, rise and fall, increase and decrease, inward and outward, profit and loss, etc., all indicate opposite meanings.

For example, rising 9 meters and descending 3 meters are opposite quantities, and rising 9 meters and falling 7 meters are also a pair of opposite meanings, that is, there are countless quantities with opposite meanings.

"Quantity with opposite meaning" means that we define the quantity of one meaning as "positive" and the quantity of another meaning opposite to "negative".

Quantities of opposite meanings contain two levels of meaning: first, they have opposite symbolic meanings; The second is that they both denote a certain quantity (in terms they are not necessarily the same). For example, the water level of a reservoir is rising and the meter is falling, two quantities with the same meaning.

If the rising rice is recorded as +m, then the falling rice is the m.

For example, it is customary to define quantities above zero, rising, eastward, forward, income, above sea level, etc., as positive, and negative as quantities with the opposite meaning, such as below zero, falling, westward, retreating, expenditure, below sea level, etc.

It reads as follows:

1: A quantity in the opposite sense is two numbers in different directions relative to the datum point (0 point), and it doesn't matter whether their absolute values are equal or not.

For example: +100 and -10 are quantities of opposite significance, and +50 and -50 are also quantities of opposite significance. (Whether the numbers are the same or not does not affect the amount of the opposite meaning).

2: In a pair of quantities with opposite meanings, if one of them is specified as positive, then the other is denoted as negative.

For example: $10 for income and $10 for expenses. (Total: Income +10, Expenses -10).

3: Quantities of opposite meanings are two numbers that represent the same meaning.

For example: a 2 cm increase in height and a 2 kg loss in weight. (2 cm for height and 2 kg for weight, not the amount in the opposite sense).

1) Realize that negative numbers are generated in production and life, and use positive and negative numbers to express quantities with opposite meanings, and be able to classify rational numbers as required.

2) A negative number is the opposite of a positive number. In real life, we often use positive and negative numbers to represent two quantities with opposite meanings. In summer, the temperature in Wuhan is as high as 42°C, you will think that Wuhan is indeed like a furnace, and in winter, the temperature in Harbin is -32°C, a minus sign makes you feel the cold of the northern winter.

3) Ancient Chinese mathematicians used to use different colors to distinguish them, in ancient times it was called "positive calculation black, negative calculation red" Nowadays, this method still uses the so-called "deficit" when keeping accounts.

For example, your regular weight (as you often know) is 60 kilograms, and you play a game of football after school in the afternoon, and you come home and weigh only 58 kilograms, which is "2 kilograms less" than your regular weight; After dinner, I drank some water, slept a little, ate breakfast again, drank soy milk, and weighed 61 kilograms, which is "1 kilogram more" than the regular weight. The "2 kg less" and "1 kg more" are the opposite of your regular weight.

On the contrary, the amount of money is very large, the temperature rises and falls, the balance of the bank's arrears, and the business makes a profit,。。 Wait a minute.

The concept of a quantity of opposite meaning is two numbers, their positive and negative signs are opposite, representing a different orientation relative to the datum point 0 point, and theirAbsoluteIt doesn't matter if it's equal or not.

The opposite number of the ruler corresponding to it.

Opposite numbers are opposites of positive and negative signs, and absolute values must also be equal. When it comes to the numbers you are talking about, +5 and -4 are quantities in opposite senses, but they are not opposites. 5 and -5 are both quantities and numbers of opposite meanings.

Methods of learning mathematics

Mathematics requires proficiency in calculations, so there are a certain amount of practice problems after class, and only through practice can you have computing ability. You should do a good job of preview before class, so that you can better digest and absorb the knowledge points that you don't know when you take math class. Mathematical formulas.

You must memorize it, and you must be able to derive and draw inferences.

Mathematics focuses on solving problems, and when you start to learn knowledge, you must understand it. Therefore, you should listen carefully in class and see how the teacher explains.

<>1. Above 10 degrees Celsius.

and minus 10 degrees Celsius;

2. Income of 100 yuan and expenditure of 100 yuan;

3. Walk 100 meters to the east and 100 meters to the west;

4. The water level rises and falls;

5. Move 500 meters to the left and 500 meters to the right;

6. Turn on the switch of the controller and turn off the switch of the controller;

7. Insert and unplug the plug;

8. The waiter said it in a funny voice and said it quietly;

9. Buy 100 bicycles and sell 100 bicycles.

Characteristics of quantities with opposite meanings:

1. The meaning expressed is opposite;

2. Both represent the same quantity, and they are quantities with the same attributes, but the values are not necessarily equal.

Because the quantity of the opposite meaning contains two meanings:

One is that they have opposite meanings and opposite symbols;

The second is that they both denote a certain quantity (in terms they are not necessarily the same).

For example, the rising meter and the falling meter of the water level of the reservoir are two quantities with opposite meanings, if the rising meter is recorded as +m, then the falling meter should be recorded as the meter, and the two numbers with the opposite sign of the equal absolute value are opposite to each other For example, -2 and +2 are opposite to each other. Obviously, the difference between the two concepts is not only that the former represents two quantities and the latter represents two numbers, but also that the absolute values of the former can be unequal, and the absolute values of the latter two numbers must be equal