Given:
P = Set of all triangles,
Q = Set of scalene triangles,
R = Set of isosceles triangles and
S = Set of equilateral triangles.
To find:
Which of the following statements are true or false?
Solution:
We know that,
Scalene triangles : All sides are different.
Isosceles triangles : Two sides are equal.
equilateral triangles : All sides are equal.
Set of all triangles contains all scalene triangles. So, set of scalene triangles Q is a subset of Set of all triangles P.
[tex]Q\subset P[/tex]
So, (a) is true.
All isosceles triangles are not equilateral triangles. So, set of isosceles triangles R is not a subset of set of equilateral triangles S.
[tex]R\nsubseteq S[/tex]
So, (b) is false.
Set of all isosceles triangles contains all equilateral triangles. So, set of equilateral triangles S is a subset of set of isosceles triangles R .
[tex]S\subset R[/tex]
So, (c) is true.