Three Dimensional Geometry Question 373
Question: The line, $ \frac{x-2}{3}=\frac{y+1}{2}=\frac{z-1}{-1} $ intersects the curve $ xy=c^{2},z=0 $ if c is equal to
Options:
A) $ \pm 1 $
B) $ \pm \frac{1}{3} $
C) $ \pm \sqrt{5} $
D) None
Show Answer
Answer:
Correct Answer: C
Solution:
[c] We have, z = 0 for the point where the line intersects the curve. Therefore, $ \frac{x-2}{3}=\frac{y+1}{2}=\frac{0-1}{-1} $
$ \Rightarrow \frac{x-2}{3}=1 $ and $ \frac{y+1}{2}=1 $
$ \Rightarrow x=5 $ and y=1 Put these value in $ xy=c^{2}, $ we get $ 5=c^{2} $
$ \Rightarrow c=\pm \sqrt{5} $
BETA
