Types of sets ( equal sets and equivalent sets)

 Types of sets

1) Equal set

=> If all the elements of two sets are equal, then they are called equal set.

Example:-

i) A= { 1,2}

   B= { x : x^2 - 3x+2 =0 , x∊ R}

finding the roots of x^2 - 3x+2 =0 by splitting the middle term method

x^2- 3x+2 =0

x^2 - [2x+x] + 2 =0

x^2 -2x -x + 2=0

x(x-2) -1(x-2) =0 

(x-2) (x-1)

x= 2 , x=1

therefore we get to know that set A= set B

ie, A={1,2} and B={1,2}

2) Equivalent set 

=> If cardinal no. of sets are equal , then they are said to be equivalent sets.

Example:-

C={1,2} & D={x,y} , n(C) = 2 and n(D) = 2 , therefore n(C)=n(D).

Note:- All equal sets are equivalent sets.