यदि \(x=2+\sqrt{5}\), तो \(x^2-4x-1\) का मान क्या होगा?
If \(x=2+\sqrt{5}\), what is the value of \(x^2-4x-1\)?
Explanation opens after your attempt
Correct Answer
A. (0)
Concept
Since \(x-2=\sqrt{5}\), squaring gives ((x-2)2=5), so \(x^2-4x-1=0\). In exams square to remove the radical.
Why this answer is correct
The correct answer is A. (0). Since \(x-2=\sqrt{5}\), squaring gives ((x-2)2=5), so \(x^2-4x-1=0\). In exams square to remove the radical.
Exam Tip
\(x-2=\sqrt{5}\), इसलिए ((x-2)2=5) से \(x^2-4x-1=0\) मिलता है। परीक्षा में वर्ग करके अपरिमेय हटाएं।
Login to save your score, XP, coins and progress.