1. Natural numbers and basic operations

The study of natural numbers and basic operations is fundamental for understanding more advanced mathematical concepts and for solving problems in several areas, including the Enem test. This article will cover these topics in detail to help students prepare for the exam.

Natural Numbers

The natural numbers are the ones we use to count objects. They start at zero and go to infinity. In mathematical terms, the set of natural numbers is represented by N = {0, 1, 2, 3, 4, 5, 6, ...}. Every natural number has a successor, which is the next number in the sequence. For example, the successor of 2 is 3, the successor of 5 is 6, and so on.

The natural numbers are used in many areas of mathematics and science. For example, they are used to count objects, measure distances, represent quantities and much more. In addition, many mathematical concepts, such as integers, rational and real numbers, are constructed from natural numbers.

Basic Operations

The four basic math operations are addition, subtraction, multiplication, and division. They are used to combine or compare numbers in various ways.

Addition

Addition is the most basic operation in mathematics. It involves combining two or more numbers to get a total. For example, if you have 2 apples and receive 3 more, you have a total of 2 + 3 = 5 apples. Addition is a commutative operation, which means that the order of numbers does not matter (2 + 3 is the same as 3 + 2).

Subtraction

Subtraction is the opposite operation to addition. It involves taking one number from another. For example, if you have 5 apples and eat 2, you have a total of 5 - 2 = 3 apples left. Unlike addition, subtraction is not a commutative operation (5 - 2 is not the same as 2 - 5).

Multiplying

Multiplication is a form of repeated addition. For example, 3 times 2 (or 3 x 2) is the same as 2 + 2 + 2 = 6. Multiplication is a commutative operation (3 x 2 is the same as 2 x 3).

Division

Division is the opposite operation to multiplication. It involves dividing one number by another. For example, if you have 6 apples and you want to share them equally among 3 people, each person gets 6 ÷ 3 = 2 apples. Division is not a commutative operation (6 ÷ 3 is not the same as 3 ÷ 6).

In summary, mastery of natural numbers and basic operations is essential for understanding mathematics and for solving problems in many areas. With continued study and practice, students can become proficient in these skills and be well prepared for the SAT exam.

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2Rational and irrational numbers

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