Pair Of Straight Lines Question 21
Question: The angle between the lines represented by the equation $ 4x^{2}-24xy+11y^{2}=0 $ are
[MP PET 1990]
Options:
A) $ {{\tan }^{-1}}\frac{3}{4},{{\tan }^{-1}}( -\frac{3}{4} ) $
B) $ {{\tan }^{-1}}\frac{1}{3},{{\tan }^{-1}}( -\frac{1}{3} ) $
C) $ {{\tan }^{-1}}\frac{4}{3},{{\tan }^{-1}}( -\frac{4}{3} ) $
D) $ {{\tan }^{-1}}\frac{1}{2},{{\tan }^{-1}}( -\frac{1}{2} ) $
Show Answer
Answer:
Correct Answer: C
Solution:
$ \tan \theta =\pm 2\frac{\sqrt{h^{2}-ab}}{a+b}=\pm 2\frac{\sqrt{144-44}}{15}=\pm \frac{4}{3} $ .
$ \Rightarrow \theta ={{\tan }^{-1}}( \pm \frac{4}{3} ) $ .
BETA
