1 Reviewing number concepts
Summary Do you know the following?
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Numbers can be classified as natural numbers, integers, prime numbers and square numbers. When you multiply an integer by itself you get a square number (x2). If you multiply it by itself again you get a cube number (x3). The number you multiply to get a square is called the square root and the number you multiply to get a cube is called the cube root. The symbol for square root is . The symbol for cube root is 3 . A multiple is obtained by multiplying a number by a natural number. The LCM of two or more numbers is the lowest multiple found in all the sets of multiples. A factor of a number divides into it exactly. The HCF of two or more numbers is the highest factor found in all the sets of factors. Prime numbers have only two factors, 1 and the number itself. The number 1 is not a prime number. A prime factor is a number that is both a factor and a prime number. All natural numbers that are not prime can be expressed as a product of prime factors. Integers are also called directed numbers. The sign of an integer (− or +) indicates whether its value is above or below 0. Mathematicians apply a standard set of rules to decide the order in which operations must be carried out. Operations in grouping symbols are worked out first, then division and multiplication, then addition and subtraction.
Unit 1: Number
Are you able to . . . ?
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identify natural numbers, integers, square numbers and prime numbers find multiples and factors of numbers and identify the LCM and HCF write numbers as products of their prime factors using division and factor trees calculate squares, square roots, cubes and cube roots of numbers work with integers used in real-life situations apply the basic rules for operating with numbers perform basic calculations using mental methods and with a calculator.