BITSAT 2024
- Exam
- BITSAT
- Year
- 2024
- Subject
- Mathematics
- Chapter
- Complex Number
BITSAT 2024 · Mathematics · Complex Number
The modulus of the complex number z such that |z+3-i|=1 and (z)=π...
The modulus of the complex number such that and is equal to
Options
- A3
- B2
- C9
- D4
Correct answer
A. 3
Step-by-step solution
Let
Given, Above is the equation of circle with centre $\equiv(-3,1) and
\text{ radius }=1$
Also, $\arg (z)=\pi \Rightarrow \tan ^{-1}\left|\frac{y}{x}\right|=\pi\Rightarrow \quad\left|\frac{y}{x}\right|=\tan \pi=0 \Rightarrow y=0$
By Eq. (i),\begin{aligned}
\Rightarrow & x & =-3 \\
\therefore & z & =-3+0 i \\
\Rightarrow & \text{ Modulus\text{ of } } z & =3
\end{aligned}$$