Search any question & find its solution
Question:
Answered & Verified by Expert
Let \(\cos ^{-1}\left(\frac{y}{b}\right)=\log _e\left(\frac{x}{n}\right)^n\), then \(A y_2+B y_1+C y=0\) is possible for
Options:
Solution:
1566 Upvotes
Verified Answer
The correct answer is:
\(A=x^2, B=x, C=n^2\)
\(\begin{aligned}
& \text { Hint: } \frac{-1}{\sqrt{1-\frac{y^2}{b^2}}} \times \frac{1}{b} y_1=\left(\frac{n}{n \times \frac{x}{n}}\right) \\
& \Rightarrow \frac{-1 y_1}{\sqrt{b^2-y^2}}=\frac{n}{x} \\
& \Rightarrow y_1 x+n \sqrt{b^2-y^2}=0 \\
& \Rightarrow y_1+x y_2+\frac{n}{2 \sqrt{b^2-y^2}} \cdot(-2 y) y_1=0
\end{aligned}\)
\(\begin{aligned} & \Rightarrow y_1+x y_2+\frac{n^2}{x} y=0 \\ & \Rightarrow y_1 x+x^2 y_2+n^2 y=0 \\ & \Rightarrow x^2 y_2+x y_1+n^2 y=0 \\ & A=x^2, B=x, C=n^2\end{aligned}\)
& \text { Hint: } \frac{-1}{\sqrt{1-\frac{y^2}{b^2}}} \times \frac{1}{b} y_1=\left(\frac{n}{n \times \frac{x}{n}}\right) \\
& \Rightarrow \frac{-1 y_1}{\sqrt{b^2-y^2}}=\frac{n}{x} \\
& \Rightarrow y_1 x+n \sqrt{b^2-y^2}=0 \\
& \Rightarrow y_1+x y_2+\frac{n}{2 \sqrt{b^2-y^2}} \cdot(-2 y) y_1=0
\end{aligned}\)
\(\begin{aligned} & \Rightarrow y_1+x y_2+\frac{n^2}{x} y=0 \\ & \Rightarrow y_1 x+x^2 y_2+n^2 y=0 \\ & \Rightarrow x^2 y_2+x y_1+n^2 y=0 \\ & A=x^2, B=x, C=n^2\end{aligned}\)
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.