Q. 24

# Mark the Correct alternative in the following:If x + i y = (1 + i) (1 + 2 i) (1 + 3i), then x2 + y2 =A. 0B. 1C. 100D. None of these

Given that (1 + i) (1 + 2i) (1 + 3i) = x + i y …(1)

We can also say that

(1 - i) (1 - 2i) (1 - 3i) = x - i y …(2)

Multiply and divide the eq no. 2 with eq no. 1

((1)2 – (i)2)((1)2 – (2i)2)((1)2 – (3i)2) = ((x)2 – (iy)2)

x2 + y2 = 2 × 5 × 10 = 100

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Polar & Euler Form of Complex Numbers on Argand Plane32 mins
Interactive Quiz Time - Polar & Euler Form of complex number58 mins
Practice session | Argument of complex numbers61 mins
Modulus & Conjugate of Complex Number | Ready for a Quiz?48 mins
Questions on Modulus & Conjugate of Complex Number62 mins
Special Quiz on Argument of complex numbers56 mins
Polar & Euler Form of Complex Number on Argand Plane58 mins
Questions Based on Polar & Euler Form of Complex Number63 mins
Get in the world of Complex Numbers55 mins
Discussion | Miscellaneous Exercise | NCERT Chapter 5| Complex Numbers47 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses
RELATED QUESTIONS :

Evaluate.

RS Aggarwal - Mathematics

Evaluate

RS Aggarwal - Mathematics

Evaluate:

(i)

(iii) .

RS Aggarwal - Mathematics

RS Aggarwal - Mathematics

RS Aggarwal - Mathematics

If then show that

RD Sharma - Mathematics

RS Aggarwal - Mathematics

RS Aggarwal - Mathematics

RS Aggarwal - Mathematics