Expressed in letters: a+b = b+a.
2, the law of addition and association: three numbers are added, first add the first two numbers, or add the last two numbers first, and the sum is unchanged. This is the so-called law of additive association.
Expressed in letters: (a+b)+c= a +( b+c)
3. Multiplicative commutative law: two factors exchange positions and the product remains unchanged. This is the so-called multiplication commutative law.
Expressed in letters: a× b = b× a.
4. Multiplication and association law: When three numbers are multiplied, the first two numbers are multiplied first, or the last two numbers are multiplied first, and the product remains unchanged. This is the so-called law of multiplication and association.
Expressed in letters: (a×b)×c= a×( b×c)
5. Multiplication and distribution law: the sum of two numbers is multiplied by one number. You can multiply them by this number first and then add them up. This is the so-called law of multiplication and division.
Expressed in letters: (a+b)×c= a×c+b×c? Answer? ×( b+c)？ =a×b+a×c？
(a-b)×c= a×c-b×c a？ ×( b-c)？ =a×b-a×c
Extended data
Related attributes:
1, the essence of subtraction: one number subtracts two numbers continuously, and the sum of these two subtractions can be subtracted.
Expressed in letters: A-B-C = A-(B+C) A-(B+C) = A-B-C.
2. If a number subtracts two numbers continuously, you can subtract the second subtraction first, and then subtract the first subtraction.
Expressed in letters: A-B A-B-C = A-C-b C–B.
3. The essence of division: a number is divided by two numbers continuously, and can be divided by the product of these two divisors.
Expressed in letters: a ÷ b ÷ c = a ÷ (b× c) a ÷ (b× c) = a ÷ b ÷ c c.
4. If a number is divisible by two numbers in succession, it can be divisible by the second divisor first and then by the first divisor.
Expressed in letters: a \b \c = a \c \b