BITSAT 2019
- Exam
- BITSAT
- Year
- 2019
- Subject
- Mathematics
- Chapter
- Complex Number
BITSAT 2019 · Mathematics · Complex Number
The value of λ for which the loci argz = (π)/(6) and | z - 2 3 i |...
The value of for which the loci and on the argand plane touch each other is&
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
z = x + iyargz = \tan^{- 1} \left(\dfrac{y}{x}\right)
tan⇒ x = y| z - 2 i | = \lambda| x + iy - 2 i | = \lambdax^{2} + \left( y - 2\sqrt{3}\right)2 = {λ}^{2}
This is the equation of circle whose centre y = 0( 0, 2 and r = \lambda∴ \lambda = \left|\dfrac{0 - \sqrt{3}\left(2\sqrt{3}\right)}{1 + 3}\right|
=3∴ \lambda = 3