integer
Integer is the most basic number in mathematics, including positive integer, negative integer and 0. We can add, subtract, multiply and Divison integers by the following steps:
1. addition: add the absolute values of two integers, and then determine the sign of the result according to the signs of the two numbers.
For example: (-3)+5=2, (-3)+(-5)=-8, 3+(-5)=-2, 5+(-5)=0.
2. subtraction: add the reciprocal of the minuend, that is, a-b=a+(-b).
For example: 5-3=2, (-5)-(-3)=-2, 3-(-5)=8, (-5)-5=- 10.
3. Multiplication: Multiply the absolute values of two integers, and then determine the sign of the result according to the signs of the two numbers.
For example: (-3)×5=- 15, (-3)×(-5)= 15, 3×(-5)=- 15, 5×(-5)=-25.
4. Division: Divide the dividend by the divisor, and then determine the sign of the result according to the signs of the two numbers.
For example: (-15)÷5=-3, (-15) ÷ (-5) = 3,15 ÷ (-5) =- 3,5 ÷ (-5).
rational number
Rational number is a general term for integers and fractions, including positive rational number, negative rational number and 0. We can add, subtract, multiply and Divison rational numbers through the following steps:
1. addition: change the denominators of two rational numbers into the same denominator, and then add the molecules.
For example: (-3/4)+(5/4)=2/4= 1/2, (-3/4)+(-5/4)=-8/4=-2, 3/4+(-5/4) =-2/.
2. subtraction: add the reciprocal of the minuend, that is, a-b=a+(-b).
For example: 5/4-3/4=2/4= 1/2, (-5/4)-(-3/4) =-2/4, 3/4-(-5/4) = 8.
3. Multiplication: Multiply the numerator and denominator of two rational numbers respectively, and then divide them.
For example: (-3/4) × (5/4) =-15/16, (-3/4) × (-5/4) =15/6, 3/4.
4. Division: the dividend is multiplied by the reciprocal of the dividend, and then divided by the dividend.
For example: (-15/4) ÷ (5/4) =-15/20 =-3/4, (-15/4) ÷ (-5/4) =/kloc-.
mark
Fraction is a representation in mathematics, which consists of a numerator and a denominator. The denominator represents the number of equal parts, and the numerator represents the number of equal parts. We can add, subtract, multiply and divide fractions by the following steps:
1. addition: change the denominator of two fractions into the same denominator, and then add the numerator.
For example: 3/4+5/4=8/4=2, 3/4+ 1/2=5/8, 1/3+2/3= 1.
2. subtraction: add the reciprocal of the minuend, that is, a-b=a+(-b).
For example: 5/4-3/4=2/4= 1/2, 3/4- 1/2= 1/4, 2/3- 1/3.
3. Multiplication: Multiply the numerator and denominator of two fractions respectively, and then divide them.
For example: 3/4×5/4= 15/ 16, 3/4× 1/2=3/8, 1/3×2/3=2/9.
4. Division: the dividend is multiplied by the reciprocal of the dividend, and then divided by the dividend.
For example: 3/4÷5/4=3/5, 3/4÷ 1/2=3/2, 1/3÷2/3= 1/2.
decimal
Decimal system is the representation of fractions. The numerator is divided by the denominator to get a decimal point, and the number after the decimal point represents the equal part of the fraction. We can add, subtract, multiply and divide decimals by the following steps:
1. addition: align the decimal points of two decimal places, and then add the numbers in the corresponding positions.
For example: 0.75+0.25= 1, 0.75+0.5= 1.25, 0.333+0.667= 1.
2. subtraction: add the reciprocal of the minuend, that is, a-b=a+(-b).
For example: 0.75-0.25=0.5, 0.75-0.5=0.25, 0.667-0.333=0.334.
3. Multiplication: Multiply two decimal places and keep the corresponding decimal places.
For example: 0.75×0.25=0. 1875, 0.75×0.5=0.375, 0.333×0.667=0.222.
4. Division: Divide the dividend by the divisor, and then keep the corresponding decimal places.
For example: 0.75÷0.25=3, 0.75 ÷ 0.5 =10.5, 0.667÷0.333=2.
algebraic expression
Algebraic expression is a representation in mathematics, which consists of variables and constants and can be added, subtracted, multiplied and divided. We can add, subtract, multiply and Divison algebraic expressions by the following steps:
1. Addition: Add the coefficients of similar items, and then merge the results.
For example: 3x+4x=7x, 2y+3y=5y, 2x+3y+4x+5y=6x+8y.
2. subtraction: add the reciprocal of the minuend, that is, a-b=a+(-b).
For example: 4x-3x=x, 3y-2y=y, 2x+3y-4x-5y=-2x-2y.
3. Multiplication: Multiply each term of two algebraic expressions, and then merge the results.
For example: (3x+2) (4x-5) =12x2-7x-10, (2y-3) (3y+4) = 6y 2+5y- 12, (2x+3y) (4x.
4. Division: Divide the dividend by the divisor, and then merge the results.
For example: (12x2-7x-10)/(3x+2) = 4x-5, (6y 2+5y- 12)/(2y-3) = 3y+4, (8x 2+).
equation
Equation is a form of equation, which consists of unknown and known numbers. The unknown can be solved by deformation.