profile-img
Aditi Agrawal posted an Question
July 07, 2020 • 01:15 am 30 points
  • IIT JAM
  • Physics (PH)

Please solve question 6.

WIIere nm AIS 6. Find the roots of the equation x + 8 = 0. Ans. 2 cos +i sin | | where n - 0, 1, 2. 3

2 Answer(s) Answer Now
  • 0 Likes
  • 3 Comments
  • 0 Shares
  • comment-profile-img>
    Ravi prakash yadav Best Answer

    x^3=-8 has solution x=-2. But it's a cubic equation hence it will have three roots. It's other two roots are complex no.s. In order to find that simply write x in Euler form and solve it to find 'r' and 'theta' using de moivre theorem. Refer to the attached solution for more understanding.

    cropped126533593055848996.jpg
whatsapp-btn

Do You Want Better RANK in Your Exam?

Start Your Preparations with Eduncle’s FREE Study Material

  • Updated Syllabus, Paper Pattern & Full Exam Details
  • Sample Theory of Most Important Topic
  • Model Test Paper with Detailed Solutions
  • Last 5 Years Question Papers & Answers