- Books Name
- CBSE Class 7 Mathematics Book
- Publication
- Param Publication
- Course
- CBSE Class 7
- Subject
- Mathmatics
Multiplication of Integers:
(i) Rule for multiplication between integers of opposite sign - When integers with opposite signs are multiplied, the result will be the product of the integers with negative sign on the product. In general for any two positive integers a and b we can say, a a x (- b) = (- a) x b = - (a x b)
Ex. – 4 x 5 = –(4 x 5) = –20
4 x –5 = –(4 x 5) = –20
(ii) Rule for multiplication between integers of same sign - When integers with same sign are multiplied, the result will be the product of integers with positive sign on the product. In general, for any two positive integers a and b, (- a) x (- b) = a x b
Ex. –5 × –4 = 20
5 × 4 = 20
(a) The product of two negative integers is a Positive integer.
Ex. (-4) x (-7) = 28
(b) The product of three negative integers is a Negative integer.
Ex. (-4) x (-7) x (-1) = -28
(c) The product of four negative integers is a Positive integer.
Ex. (-4) x (-7) x (-1) x (-2) = 56