1, first calculate the power, then multiply and divide, and finally add and subtract.
2. If there are brackets, count the inside of brackets first, and then count the outside of brackets.
3. If there are multiple brackets, it should be calculated from outside to inside.
For example, for an expression 2×(3+4-5), you should first calculate the addition and subtraction in brackets to get (3+4-5)=2, and then multiply it to get 2×2=4.
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Rational number is one of the most basic concepts in our mathematics study. It is a general term for integers and fractions. Rational numbers include all integers and fractions, in which fractions are composed of numerator and denominator, and numerator and denominator are integers. Rational numbers play a very important role in mathematics. It is the basis for us to understand integers, fractions and decimals, and it is also the cornerstone for all kinds of mathematical operations and solving practical problems.
The mixed operation of rational numbers is an important mathematical skill, including basic operations such as addition, subtraction, multiplication and division. In the mixed operation of rational numbers, we need to follow a certain operation order to ensure the accuracy and order of calculation.
First of all, we should make clear the basic order of rational number mixing operation. According to mathematical rules, the mixed operation of rational numbers should first calculate the power, then multiply and divide, and finally add and subtract. If there are brackets, count the inside of the brackets first, and then the outside of the brackets. For multiple brackets, it should be calculated from outside to inside.
Secondly, we should master the basic skills of rational number mixing operation. In the calculation, we should try our best to simplify the calculation process by using mathematical laws such as distribution law and combination law. At the same time, we should also pay attention to the symbol problem to avoid mistakes. For example, when calculating (-2)+(-3), first make sure that the symbol is negative, and then calculate the absolute value of 5.
In addition, we should learn how to use rational numbers to solve practical problems. Rational numbers are widely used in real life, such as measurement, calculation and statistics. We can solve these problems through the operation of rational numbers, such as calculating area, volume and temperature.