Circle And System Of Circles Question 332
Question: The equation of the tangent at the point $ ( \frac{ab^{2}}{a^{2}+b^{2}},\frac{a^{2}b}{a^{2}+b^{2}} ) $ of the circle $ x^{2}+y^{2}=\frac{a^{2}b^{2}}{a^{2}+b^{2}} $ is
Options:
A) $ \frac{x}{a}+\frac{y}{b}=1 $
B) $ \frac{x}{a}+\frac{y}{b}+1=0 $
C) $ \frac{x}{a}-\frac{y}{b}=1 $
D) $ \frac{x}{a}-\frac{y}{b}+1=0 $
Show Answer
Answer:
Correct Answer: A
Solution:
From formula of tangent at a point, $ x( \frac{ab^{2}}{a^{2}+b^{2}} )+y( \frac{a^{2}b}{a^{2}+b^{2}} )=\frac{a^{2}b^{2}}{a^{2}+b^{2}}\Rightarrow \frac{x}{a}+\frac{y}{b}=1 $ .
BETA
