Integers
Natural numbers: 1, 2, 3, 4, 5, …………………
Whole numbers: 0, 1, 2, 3, 4, 5, ……………….. (Adding 0 to natural numbers)
Positive integers: 0, 1, 2, 3, 4, 5, ………………
Negative integers: -1, -2, -3, -4, -5, …………………
Integers: ……….,-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5,……… (Combination of positive and negative integers)
Just keep in mind that
+ (+) = +
+ (-) = –
– (-) = +
– (+) = –
Addition of integers:
having same sign (+)
Example: 9 + (+3) = 9 + 3 = 12
having same sign (-)
Example: (-9) + (-3) = – 9 – 3 = – 12
having different sign (one + and one -)
Example: – 9 + (+3) = – 9 + 3 = – 6 (sign of larger digit)
Subtraction of integers:
having same sign (+)
Example: 9 – (+3) = 9 – 3 = 6 (sign of larger digit)
having same sign (-)
Example: (-9) – (-3) = – 9 + 3 = – 6 (sign of larger digit)
having different sign (one + and one -)
Example: – 9 – (+3) = – 9 – 3 = – 12
Multiplication of integers:
having same sign (+)
Example: 9 x (+3) = 9 x 3 = 27 ………..[(+) x (+) = +]
having same sign (-)
Example: (-9) x (-3) = 27 …………….[(-) x (-) = +]
having different sign (one + and one -)
Example: – 9 x (+3) = – 27 ……….[(-) x (+) = -]