Integers

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Integers

The Integers are the numbers which can be positive, negative or zero, but cannot be a fraction.

These numbers are used to perform various Arithmetic Operations, like addition, subtraction, multiplication and division.

The integers are represented by symbol ‘Z’. Z = {…-3,-2,-1,0,1,2,3,..}

Type of Numbers

Operation

Result

Example

Positive + Positive

Add

Positive (+)

10 + 15 = 25

Negative + Negative

Add

Negative (-)

(-10) + (-15) = -25

Positive + Negative*

Subtract

Positive (+)

(-10) + 15 =5

Negative + Positive*

Subtract

Negative (-)

10 + (-15)= -5

* : Sign of larger number.

Multiplication of Integers:

Operation

Resultant Sign

Example

(+) x (+)

+

5 x 3 = 15

(+) x (-)

-

5 x -3 = -15

(-) x (+)

-

-5 x 3 = -15

(-) x (-)

+

-5 x -3 = 15

Note:

When two positive integers are multiplied then the result is positive.

When two negative integers are multiplied then also the result is positive.

But when one positive and one negative integer is multiplied, then the result is negative.

When there is no symbol, then the integer is positive.

Additive Inverse of a number is the number multiplied by -1.

- So, -5 is additive inverse of 5.

- Number + Additive inverse = 0

e.g. 7 + Additive Inverse of 7 i.e. -7 is 7 + (-7) = 7 – 7 = 0

Reciprocal of an integer is obtained by dividing 1 by that integer.

Reciprocal is also called as Multiplicative Inverse.

e.g. Reciprocal or Multiplicative Inverse of 3 is 1/3.