These Complex Numbers And Quadratic Equations MCQs and Answers are most important for your upcoming examinations including JEE Main & JEE Advanced. These Complex Numbers And Quadratic Equations MCQs and Answers will help you to score good marks in your exams by helping you to prepare the concepts better and hence, help you to understand the concepts more clearly.

## Complex Numbers And Quadratic Equations MCQs and Answers

1. If the area of the triangle on the complex plane formed by the points z, iz and z + iz is 50 square units, then |z| is

(A) 5

(B) 10

(C) 15

(D) None of these

**Answer:** 10

2. If z = x + iy and w = 1 – iz / z – i , then | w | = 1 implies that, in the complex plane,

(A) z lies on the imaginary

(B) z lies on the real axis

(C) z lies on the unit circle

(D) None of these

**Answer:** z lies on the real axis

3. The argument of (1 – i√3)/(1 + i√3) is

(A) π/3

(B) 2π/3

(C) 7π/3

(D) 4π/3

**Answer:** 4π/3

4. The roots of the equation x^{2} + x + 1 = 0 is

(A) {1 ± i√3}/2

(B) {-1 ± i√3}/2

(C) {i ± √3}/2

(D) {-i ± √3}/2

**Answer:** {-1 ± i√3}/2

5. The value of i + i^{2} + i^{3} + i^{4} is

(A) 0

(B) 1

(C) -1

(D) 2i

**Answer:** 0

6. If α is cube root of unity, then for n ∈ N, the value of α^{3n + 1} + α^{3n + 5} is

(A) -1

(B) 0

(C) 1

(D) 3

**Answer:** -1

7. The inequality | z – 2 | < | z – 4 | represents the region given by

(A) Re (z) > 0

(B) Re (z) < 3

(C) Re (z) > 2

(D) none of these

**Answer:** Re (z) < 3

8. Let z = a + ib and if |z| = 0 then

(A) Real(z) = 0

(B) Imaginary(z) = 0

(C) Real(z) = Imaginary(z) = 0

(D) None of these

**Answer:** Real(z) = Imaginary(z) = 0

9. The equation whose roots are 7i and 2i is

(A) x^{2} + (9i)x – 14 = 0

(B) x^{2} – (9i)x + 14 = 0

(C) x^{2} – (9i)x – 14 = 0

(D) x^{2} + (9i)x + 14 = 0

**Answer:** x^{2} – (9i)x – 14 = 0

10. The locus of the point z satisfying Re(z2 ) = 0 is

(A) A pair of striaght line

(B) a circle

(C) a rectangular hyperbola

(D) None of these

**Answer:** A pair of striaght line