## NCERT Solutions for Class 12 Maths Chapter 9 – Differential Equations Ex 9.1

#### Question 1:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is four.
The given differential equation is not a polynomial equation in its derivatives. Hence, its degree is not defined.

#### Question 2:

Determine order and degree(if defined) of differential equation

The given differential equation is:
The highest order derivative present in the differential equation is. Therefore, its order is one.
It is a polynomial equation in. The highest power raised tois 1. Hence, its degree is one.

#### Question 3:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the given differential equation is. Therefore, its order is two.
It is a polynomial equation inand. The power raised tois 1.
Hence, its degree is one.

#### Question 4:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the given differential equation is. Therefore, its order is 2.
The given differential equation is not a polynomial equation in its derivatives. Hence, its degree is not defined.

#### Question 5:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is two.
It is a polynomial equation inand the power raised tois 1.
Hence, its degree is one.

#### Question 6:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is three.
The given differential equation is a polynomial equation in.
The highest power raised tois 2. Hence, its degree is 2.

#### Question 7:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is three.
It is a polynomial equation in. The highest power raised tois 1. Hence, its degree is 1.

#### Question 8:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is one.
The given differential equation is a polynomial equation inand the highest power raised tois one. Hence, its degree is one.

#### Question 9:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is two.
The given differential equation is a polynomial equation inandand the highest power raised tois one.
Hence, its degree is one.

#### Question 10:

Determine order and degree(if defined) of differential equation

The highest order derivative present in the differential equation is. Therefore, its order is two.
This is a polynomial equation inandand the highest power raised tois one. Hence, its degree is one.

#### Question 11:

The degree of the differential equation
is
(A) 3 (B) 2 (C) 1 (D) not defined

The given differential equation is not a polynomial equation in its derivatives. Therefore, its degree is not defined.
Hence, the correct answer is D.

#### Question 12:

The order of the differential equation
is
(A) 2 (B) 1 (C) 0 (D) not defined