I. Separability
Divisibility means that the quotient obtained by dividing the integer A by the natural number B is exactly an integer and the remainder is zero. Suppose A is divisible by B (or B is divisible by A), which is recorded as b|a and read as "B is divisible by A" or "A is divisible by B". It is different and related to division. Division refers to the quotient obtained by dividing the exponent a by the number b(b≠0)
Therefore, the difference between divisibility and division is that divisibility is only when divisor, divisor and quotient are integers and the remainder is zero. Division is not limited to integer range, divisor, divisor and quotient can be integers or finite decimals, as long as the remainder is zero. The relationship between them is that divisibility is a special case of division.
Second, the characteristic formula of divisibility.
If the last digit of an integer is 0, 2, 4, 6 or 8, the number can be divisible by 2. If the sum of the numbers of an integer is divisible by 3, then the integer can be divisible by 3. If the last two digits of an integer are divisible by 4, then this number is divisible by 4. If the last digit of an integer is 0 or 5, then the number can be divisible by 5. If the sum of digits of an integer is divisible by 3 or 9, then the number can be divisible by 3 or 9.
Third, the basic methods and skills of learning mathematics
1, and establish a solid mathematical foundation.
Learning mathematics needs a solid foundation, so before you start learning mathematics, you need to master basic knowledge such as arithmetic, algebra, geometry and trigonometry. Only by establishing a solid mathematical foundation can we better understand more advanced mathematical knowledge.
3. Do more exercise.
Mathematics needs constant practice in order to master knowledge better. Therefore, when learning mathematics, we should do more exercises, especially those involving difficulties and key points. Through constant practice, you can find and correct your mistakes and improve your ability.
3, master the problem-solving methods
When learning mathematics, we should pay attention to mastering the problem-solving methods. Different mathematical problems need different methods to solve, so we should learn to analyze the problems and find the most suitable method to solve them. At the same time, we should learn to use mathematical knowledge and apply what we have learned to practical problems.