What does C mean in mathematics? In daily life, when we study mathematics at school, we will know all kinds of letters, and different letters have certain meanings in mathematics. Let's share the meaning of c in mathematics.

The meaning of c in mathematics 1 C represents a complex set in mathematics. It is often used as a symbolic expression of text description ellipsis in mathematical calculation and other occasions.

The set of complex numbers is represented by C, and the set of real numbers is represented by R. Obviously, R is the proper subset of C, and the set of complex numbers is out of order, so the order of size cannot be established. The value of the positive square root of the square sum of the real part and imaginary part of a complex number is called the module of the complex number, which can be written as ∣z∣.

Generally, numbers in the form of z=a+bi are called complex numbers, where A is called the real part, B is called the imaginary part, and I is called the imaginary part. When the imaginary part is equal to zero, this complex number can be regarded as a real number; When the imaginary part of z is not equal to zero and the real part is equal to zero, z is often called pure imaginary number. Complex number field is an algebraic closure of real number field, that is, any polynomial with complex coefficients always has roots in complex number field.

Letters representing complex sets:

N in mathematics: nonnegative integer set or natural number set {0, 1, 2, 3, …}

N* or N+: positive integer set {1, 2,3, …}

Z: integer set {…,-1, 0, 1, …}

Q: Rational number set

Q+: Set of Positive Rational Numbers

Q-: set of negative rational numbers

R: set of real numbers (including rational numbers and irrational numbers)

R+: positive real number set

R-: negative real number set

C: complex set

The meaning of c in mathematics 2 C means combination.

Combination is a mathematical term. Taking m(m≤n) elements from n different elements as a group is called taking out the combination of m elements from n different elements.

For example, the following questions:

There is enough wood 3, 4, 5, 6, 7 meters long. Take three pieces to form a triangle. How many different triangles can you form?

Calculation method:

C is 3 in the upper right corner and 5 in the lower right corner, which means choosing three things from five things (in no particular order).

5! /3! *(5-3)! =1* 2 * 3 * 4 * 5/1* 2 * 3 *1* 2 =10 The sum of any two sides is greater than the third side.

That is, the combination of three numbers selected from five numbers is 10, minus the invalid (3,4,7)1.

Add 5*4=20 isosceles triangles, subtract (3,3,6) and (3,3,7), there are 5 equilateral triangles, and one * * * has 9+ 18+5=32.

Extended data:

One of the important concepts of combinatorial mathematics. Taking out M different elements (0≤m≤n) from N different elements at a time and synthesizing a group regardless of their order is called selecting the combination of M elements from N elements without repetition. The total number of all such combinations is called the combination number, and the calculation formula of this combination number is

or

The combination obtained by repeatedly extracting m elements from N-ary set A is essentially an M-ary subset of A ... If set A is ordered,

Become an ordered set, then the combination of m elements extracted from A corresponds to several segments.

Strict order-preserving mapping of ordered set a, combination number

Commonly used symbols are

Math C. Meaning 3 What does each letter stand for in mathematics?

Perimeter c, the integral of the perimeter of the edge of a finite area, is called perimeter and is the length of a graph. The perimeter of a polygon is also equal to the sum of all sides of the graph, the perimeter of a circle =πd=2πr (d is the diameter, R is the radius, π), and the perimeter of a sector = 2R+nπR÷ 180 (n= central angle) = 2R+kR (k= radian).

Area S. When the space occupied by an object is a two-dimensional space, the size of the occupied space is called the area of the object, which can be plane or curved. Square meter, square decimeter and square centimeter are recognized units of area, which can be expressed in letters as (m, dm, cm).

Area is a quantity indicating the degree of a two-dimensional figure or shape or plane layer in a plane. A surface region is a simulation on a two-dimensional surface of a three-dimensional object. Area can be understood as the amount of material with a given thickness, which is necessary to form a shape model.

Area bisector

There are countless lines bisecting the triangle area. Three of them are the median of the triangle (connecting the midpoint of both sides and the opposite vertex), and they are collinear at the center of gravity of the triangle;

In fact, they are the only area bisectors passing through the center of gravity. Any line that divides the area and perimeter of a triangle into two halves can pass through the entrance of the triangle (the center of its perimeter). For any given triangle, there are one, two or three triangles.

Any line passing through the midpoint of the parallelogram divides the area in two. All bisectors of the area of a circle or other ellipse pass through the center, and any chord passing through the center bisects the area. For circles, they are the diameter of the circle.