The document discusses various properties of operations on rational numbers. It states that rational numbers are closed under addition, subtraction, multiplication and division. This means these operations on rational numbers always yield a rational number as the result. It also discusses properties like commutativity, associativity and distributivity that apply to some operations but not others. For example, addition and multiplication of rational numbers are commutative but subtraction and division are not.
10. Additive identity for rational
number is 0 as
𝑎
𝑏
+ 0 =
𝑎
𝑏
Example :-
2
3
+ 0 =
2
3
∴thus when we add 0
to rational number
its answer is the
number itself.
Additive identity for rational
number is 0 as
𝑎
𝑏
+ 0 =
𝑎
𝑏
Example :-
2
3
+ 0 =
2
3
11. Additive inverse for rational
number is
𝑎
𝑏
+(-
𝑎
𝑏
)=0
Example :-
2
3
+ (-
2
3
)=0
∴thus for an rational
number
𝑎
𝑏
there exists
its opposite (-
𝑎
𝑏
) such
that there sum is zero,
(-
𝑎
𝑏
) is additive inverse
27. ∴thus when we
multiply 1 to
rational number its
answer is the number
Multiplicative identity for rational
number is 1 as
𝑎
𝑏
× 1 =
𝑎
𝑏
Example :-
2
3
× 1 =
2
3
28. If
𝑎
𝑏
is a rational number then
𝑎
𝑏
×
𝑏
𝑎
=1
Example :-
2
3
×
3
2
=1
∴thus for an rational
number
𝑎
𝑏
there exists
its opposite
𝑏
𝑎
such that
there product is 1,
𝑏
𝑎
is
additive inverse for
𝑎
.