ExamBro
ExamBro
JEE Mains · Maths · STD 11 - 4.1 complex nubers

Let \(z\) be a complex number such that \(\left| z \right| + z = 3 + i\) (where \(i = \sqrt { - 1} \)). Then \(\left| z \right|\) is equal to

  1. A \(\frac{{\sqrt {34} }}{3}\)
  2. B \(\frac{5}{3}\)
  3. C \(\frac{{\sqrt {41} }}{4}\)
  4. D \(\frac{5}{4}\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(\frac{5}{3}\)

Step-by-step Solution

Detailed explanation

\(z\, = \,x\, + \,iy\) \(\sqrt {{x^2} + {y^2}} \, + \,x\, + \,iy\, = \,3\, + \,i\) \( \Rightarrow \,y = 1\) \(\sqrt {{x^2} + 1} \, + \,x = 3 \Rightarrow {x^2}\, + \,1 = 9 - 6x + {x^2}\) \( \Rightarrow \,x = \frac{4}{3}\) \(|z|\, = \,\sqrt {{x^2}\, + \,{y^2}} \, = \,\frac{5}{3}\)
From JEE Mains
Explore more questions on app