Comparison of rational numbers in junior one math formulas: a=0, | a | = 0a>0, | a | = aa<0, | a | =-a | a |>；; |b|, a<0, b<0, and then.
Additive commutative law: a+b=b+a Addition Law: (a+b)+c=a+(b+c) Subtraction: a-b=a+(-b) Multiplication Commutation Law: ab=ba Multiplication Law: (ab)c=a(bc) Division: A \
Angle and Line-There is one and only one straight line in the same plane perpendicular to the known straight line, and the vertex angles are the same. In the same plane, one and only one straight line is parallel to the known straight line through a point outside the straight line. If both lines are parallel to the third line, then the two lines are also parallel to each other. Two lines perpendicular to the same line are parallel to each other. Equal waist angle/equal internal angle/complementary internal angle: two straight lines are parallel; Equal waist angle/equal internal dislocation angle/complementary internal dislocation angle. Right angle = 90, 180
Two basic solutions to the equation of mathematical knowledge points in the second volume of junior one: 1. Substitution exclusion method II. Addition, subtraction and elimination method if A >；; B, then a+c > b+c，a-c & gt； B-c If a>b, c>0, then ac & gtBc if a>b, c<0, then AC.
The outer angle of a triangle is equal to the sum of two non-adjacent inner angles. The outer angle of a triangle is greater than any inner angle that is not adjacent to it. Triangles are stable. The sum of any two sides of a triangle is greater than the third side, and the difference between the two sides is less than the third side.
N= number of sides of polygon (n >；; 0) The outer angle and inner angle of the polygon are 180, and the number of sides of the polygon is 180 * (n-2). The diagonal number of a polygon is n(n-3)÷2. The inner angle of a regular polygon is 180-360.
Mathematics A2-B2 = (A+B) (A-B) A3+B3 = (A+B) (A2-AB+B2) A3-B3 = (A-B (A2+AB+B2) Trigonometric Inequality | A+B | | | A The relationship between the roots and coefficients of the solution of a quadratic equation.
The first mathematical geometry formula is that the surface area of a sphere is s=4pi*r2, the lateral area of a cylinder is s=c*h=2pi*h, the lateral area of a cone is s= 1/2*c*l=pi*r*l, the arc length formula l=a*ra is the radian of the central angle r0, and the sector area formula s =1. Pi*r2h Oblique Prism Volume v=sl Note: Where, S is the area of straight section and L is the volume of a long cylinder with sides. Formula v=s*h cylinder v=pi*r2h.
These mathematical formulas seem complicated, but they are particular about ways and means when they are recited. The above is the math formula of Grade One that I summarized for you. I hope it will be helpful to the students of Grade One.