int_0^1 dx/(sqrt(4-3x²))=?
DU.TECHউচ্চতর গণিত প্রথম পত্রযোগজীকরণsin ও cosine সংক্রান্ত যোগজ (Topic Practice)DU.TECH - ⚡ অনলাইন প্রশ্নব্যাংক দেখুন 💥
সঠিক উত্তরঃ
D.
pi/(3√3)
Explanation:

Another Explanation (5):
সমাধান: 🤔
$$\int_{0}^{1} \frac{dx}{\sqrt{4-3x^2}}$$
ধরি, \(x = \frac{2}{\sqrt{3}} \sin{\theta}\) 🤓
তাহলে, \(dx = \frac{2}{\sqrt{3}} \cos{\theta} d\theta\) 🧐
যখন \(x = 0\), \(\sin{\theta} = 0\), সুতরাং \(\theta = 0\) 😇
যখন \(x = 1\), \(\sin{\theta} = \frac{\sqrt{3}}{2}\), সুতরাং \(\theta = \frac{\pi}{3}\) 🤩
অতএব,
$$\int_{0}^{1} \frac{dx}{\sqrt{4-3x^2}} = \int_{0}^{\pi/3} \frac{\frac{2}{\sqrt{3}} \cos{\theta} d\theta}{\sqrt{4 - 3(\frac{4}{3} \sin^2{\theta})}}$$
$$= \int_{0}^{\pi/3} \frac{\frac{2}{\sqrt{3}} \cos{\theta} d\theta}{\sqrt{4 - 4\sin^2{\theta}}}$$
$$= \int_{0}^{\pi/3} \frac{\frac{2}{\sqrt{3}} \cos{\theta} d\theta}{\sqrt{4(1 - \sin^2{\theta})}}$$
$$= \int_{0}^{\pi/3} \frac{\frac{2}{\sqrt{3}} \cos{\theta} d\theta}{2\cos{\theta}}$$
$$= \frac{1}{\sqrt{3}} \int_{0}^{\pi/3} d\theta$$
$$= \frac{1}{\sqrt{3}} [\theta]_{0}^{\pi/3}$$
$$= \frac{1}{\sqrt{3}} \left(\frac{\pi}{3} - 0\right)$$
$$= \frac{\pi}{3\sqrt{3}}$$
সুতরাং, \(\int_{0}^{1} \frac{dx}{\sqrt{4-3x^2}} = \frac{\pi}{3\sqrt{3}}\) 🎉