Complex Numbers and Quadratic Equations · Class 11 · CBSE · Science Mathematics
If z = 3 - 4i, where i² = -1, then the modulus of z is
Practice question from Complex Numbers and Quadratic Equations (Class 11 · CBSE · Science Mathematics), with the correct answer and a step-by-step solution.
easy · MCQ · Q-CCB8E0
If z = 3 - 4i, where i² = -1, then the modulus of z is
- A.1
- B.5Correct answer
- C.7
- D.25
Solution
For z = a + ib, |z| = √(a² + b²). Hence, |3 - 4i| = √(3² + (-4)²) = √25 = 5.
More from Complex Numbers and Quadratic Equations
- The roots of the quadratic equation x² + 4x + 13 = 0 are
- The value of (1 + i)/(1 - i), where i² = -1, is
- Find the square roots of the complex number -7 + 24i.
- If z = 2 - 3i, where i² = -1, then z multiplied by its conjugate is
Practise more Mathematics
Sign up free for adaptive practice on this chapter, with instant feedback and hints on every question.
Start practising freeFree to start · No credit card needed