1. Tardigrade
  2. Question
  3. Mathematics
  4. AB is a chord of the parabola y2=4ax with vertex at A. BC is drawn perpendicular to AB meeting the axis at C. The projection of BC on the axis of the parabola is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. AB is a chord of the parabola $ {{y}^{2}}=4ax $ with vertex at A. BC is drawn perpendicular to AB meeting the axis at C. The projection of BC on the axis of the parabola is

JamiaJamia 2009

Solution:

In $ \Delta ABC, $ we have $ \tan \theta -\frac{y}{x} $ ...(i)
In $ \Delta BCD, $ we have $ \tan (90{}^\circ -\theta )=\frac{y}{CD} $ $ \Rightarrow $ $ CD=y\,\tan \theta =\frac{{{y}^{2}}}{x} $ [using Eq. (i)] $ \Rightarrow $ $ CD=\frac{4ax}{x}=4a $

Solution Image