Exercise 2.3
NCERT solutions for Class 9 Maths Polynomials

NCERT Solutions for Class 9 Maths Polynomials
1. Find the remainder when
is divided by
(i)
(ii) 
(iii) 
(iv) 
(v) 
Ans. (i)
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get



=-1+3-3+1
=0
Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as 0.
(ii)
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get






Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as
.
(iii)
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get


=0+0+0+1
=1
Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as 1.
(iv)
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get




Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as
.
(v)
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get







Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as
.
NCERT Solutions for Class 9 Maths Exercise 2.3
2. Find the remainder when
is divided by
.
Ans. We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
in the polynomial
, to get



= 5a
Therefore, we conclude that on dividing the polynomial
by
, we will get the remainder as
.
NCERT Solutions for Class 9 Maths Exercise 2.3
3. Check whether
is a factor of
.
Ans. We know that if the polynomial
is a factor of
, then on dividing the polynomial
by
, we must get the remainder as 0.
We need to find the zero of the polynomial
.

While applying the remainder theorem, we need to put the zero of the polynomial
inthe polynomial
, to get





We conclude that on dividing the polynomial
by
, we will get the remainder as
, which is not 0.
Therefore, we conclude that
is not a factor of
.