1. Any monomial in the form of the product of letters and numbers. In division, dividing by a number is equal to multiplying the reciprocal of this number.

2. A single letter or number is also called a monomial.

3. Letters cannot be used as denominator. (The monomial is an algebraic expression, not a fraction)

A, -5, x and 2XY are all monomials, but they are not monomials.

4,0 is also a number and a monomial.

5. Some scores are also single.

The number of single events refers to the exponential sum of all letter factors in a single event.

This noun was translated into Chinese by Li, a mathematician in Qing Dynasty, according to the concept of the original word.

The monomial is the product of letters and numbers.

Number of times of a monomial: The sum of the indices of all the letters in the monomial is called the number of times of the monomial.

Single factor: the numerical factor in a single item. For example, the coefficient of 2xy is 2; The coefficient of -5zy is -5.

The exponent of the letter T is 1, and 100t is a monomial; In monomial vt, the sum of the exponents of the letters V and T is 2, and vt is a quadratic monomial.

For example: xy, 3, a z, ab, b ... are all monomials.

A formula that associates letters or numbers representing numbers with operational symbols is called an algebraic expression.

Algebraic expressions cannot contain "≥", "=" and "

The rule of monomial writing: when the number is multiplied by the letter, the number comes before the letter; The multiplication sign can be omitted as a dot or not written; The formula of division can be written as a fractional formula; Multiply the band score with the letter, and the band score will become a false score.

How many times is the monomial? How many times is it called a monomial?

Letters cannot be in the denominator (because this is a fraction, not a monomial)

""is a known constant, written after the letter of the first number (for example:), not a letter, read pà i.

pay attention to

1.π is a constant, so it can also be used as a coefficient.

2. If the coefficient is a fraction, it should become a false fraction.

3. In the monomial, the letter can't be the denominator, but the numerator can.

4. The coefficient of single number "0" is zero, and the degree is 1.

The coefficient of a constant is itself, and the degree is zero.

The format numbers are written in front of the letters, and the multiplication sign (5a, 16xy, etc. ) should be omitted. When the coefficient of the monomial is 1 or-1, "1" is usually omitted, such as [(- 1)ab] written as [-ab] and so on.