JEE PYQ

[JEE Advanced 2010] let z 1 t z 1 tz 2 for real t in 0 1

VAVidaara Admin Asked 2d ago 0 views 1 answer

Let $z=(1-t)z_1+tz_2$ for real $t\in(0,1)$ with $z_1\ne z_2$. Which are always true?

(a) $|z-z_1|+|z-z_2|=|z_1-z_2|$
(b) $\arg(z-z_1)=\arg(z-z_2)$
(c) $\begin{vmatrix}z-z_1&\bar z-\bar z_1\\z_2-z_1&\bar z_2-\bar z_1\end{vmatrix}=0$
(d) $\arg(z-z_1)=\arg(z_2-z_1)$

1 Answer

VAVidaara Admin ✓ Vidaara Team ✓ Accepted · 2d ago ▲ 0

Correct answer: (a) $|z-z_1|+|z-z_2|=|z_1-z_2|$

$z$ lies on segment $z_1z_2$: distances add (a), $z-z_1\parallel z_2-z_1$ (d), and the collinearity determinant vanishes (c). (b) is false (the args differ by $\pi$).

JEE Advanced 2010 · Complex Numbers — verified solution by the Vidaara Team.

Log in to post your own answer or join the discussion.

Discussion (0)

No comments yet — start the discussion.

← Back to all questions