Fractions are like A/B, where A and B are algebraic expressions, B contains unknowns, and algebraic expressions where B is not equal to 0 are called fractions. Where a is called the numerator of the fraction and b is called the denominator of the fraction.

To grasp the concept of score, we should pay attention to:

The denominator of the (1) score must contain an unknown number.

(2) The value of denominator cannot be zero. If the denominator is zero, then the score is meaningless.

3。 Because letters can represent different numbers, fractions are more common than fractions.

Definition of fraction: divide the unit "1" or the whole "1" into several parts on average, and the number representing such one or several parts is called fraction. The denominator is to divide an object into several parts, and the numerator is to take several parts. Dividing the denominator into the numerator part is the 1 part.