# NCERT Maths Solutions Class 11th Chapter 5 Complex Numbers and Quadratic Equations

## Complex Numbers and Quadratic Equations Class 11 Maths NCERT Solutions

NCERT Solutions for Class 11 Maths, Chapter 5: Complex Numbers and Quadratic Equations, are highly valuable for completing your homework. These solutions, covering all exercises, have been prepared by experienced teachers at www.manabadi.co.in.

### NCERT Solutions for Class 11 Maths Chapter 5 Exercise 5.1

#### Ex 5.1 Class 11 Maths Question 1:

#### Ex 5.1 Class 11 Maths Question 2:

#### Ex 5.1 Class 11 Maths Question 3:

#### Ex 5.1 Class 11 Maths Question 4:

Express the given complex number in the form a + ib: 3(7 + i7) + i(7 + i7)

### NCERT Solutions for Class 11 Maths Chapter 5 Exercise 5.2

#### Ex 5.2 Class 11 Maths Question 1:

#### Ex 5.2 Class 11 Maths Question 2:

#### Ex 5.2 Class 11 Maths Question 3:

Converrt the given complex number in polar form:1 - i

#### Ex 5.2 Class 11 Maths Question 4:

Converrt the given complex number in polar form: - 1 + i

### NCERT Solutions for Class 11 Maths Chapter 5 Exercise 5.3

#### Ex 5.3 Class 11 Maths Question 1:

Solve the equation x^{2} + 3 = 0

**Ans:**

The given quadratic equation is x^{2} + 3 = 0

On comparing the given equation with ax^{2} + bx + c = 0, we obtain

a = 1, b = 0, and c = 3

Therefore, the discriminant of the given equation is

D = b^{2} - 4ac = 0^{2} - 4 x 1 x 3 = - 12

Therefore, the required solutions are

#### Ex 5.3 Class 11 Maths Question 2:

Solve the equation 2x^{2} + x + 1 = 0

**Ans:**

The given quadratic equation is 2x^{2} + x + 1 = 0

On comparing the given equation with ax^{2} + bx + c = 0, we obtain

a = 2, b = 1, and c = 1

Therefore, the discriminant of the given equation is

D = b^{2} - 4ac = 1^{2} - 4 x 2 x 1 = 1 - 8 = - 7

Therefore, the required solutions are

#### Ex 5.3 Class 11 Maths Question 3:

Solve the equation x^{2} + 3x + 9 = 0

**Ans:**

The given quadratic equation is x^{2} + 3x + 9 = 0

On comparing the given equation with ax^{2} + bx + c = 0, we obtain

a = 1, b = 3, and c = 9

Therefore, the discriminant of the given equation is

D = b^{2} - 4ac = 3^{2} - 4 x 1 x 9 = 9 - 36 = - 27

Therefore, the required solutions are

#### Ex 5.3 Class 11 Maths Question 4:

Solve the equation -x^{2} + x + 2 = 0

**Ans:**

The given quadratic equation is -x^{2} + x + 2 = 0

On comparing the given equation with ax^{2} + bx + c = 0, we obtain

a = -1, b = 1, and c = -2

Therefore, the discriminant of the given equation is

D = b^{2} - 4ac = 1^{2} - 4 x (-1) x (-2) = 1 - 8 = - 7

Therefore, the required solutions are

### NCERT Solutions for Class 11 Maths Chapter 5 Miscellaneous Solutions

#### Miscellaneous Exercise Class 11 Maths Question 1:

Evaluate

#### Miscellaneous Exercise Class 11 Maths Question 2:

For any two complex numbers z_{1}andz_{2} prove that