ExamBro
ExamBro
TS EAMCET · Maths · Complex Number

If \(z=x+i y\) satisfies the equation \(z^2+a z+a^2=0, a \in \mathbb{R}\), then

  1. A \(|z|=|a|\)
  2. B \(|z-a|=|a|\)
  3. C \(z=|a|\)
  4. D \(z=a\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(|z|=|a|\)

Step-by-step Solution

Detailed explanation

\(z=x+i y\) Put in \(z^2+a z+a^2=0\) \(\begin{aligned} & \Rightarrow x^2-y^2+2 i x y+a x+i y+a^2=0 \\ & \Rightarrow x^2-y^2+a x+a^2+i(2 x y+a y)=0 \end{aligned}\) Comparing imaginary part \(2 x y+a y=0 \Rightarrow x=\frac{-a}{2} \quad[\because y \neq 0]\) Comparing real part ;…