৫. i. $\cos 2 heta = \cos^{2} heta - \sin^{2} heta$ ii. $\cos 2 heta = \frac{1 - an^{2} he

Question

৫. i. $\cos 2	heta = \cos^{2} 	heta - \sin^{2} 	heta$ ii. $\cos 2	heta = \frac{1 - 	an^{2} 	heta}{1 + 	an^{2} 	heta}$ iii. $\cos 2	heta = \frac{\cot^{2} 	heta - 1}{	ext{cosec}^{2} 	heta}$ নিচের কোনটি সঠিক?

Accepted Answer

i, ii ও iii

Explanation: ত্রিকোণমিতির সকল সূত্রগুলোই সঠিক।

৫. i. $\cos 2\theta = \cos^{2} \theta - \sin^{2} \theta$ ii. $\cos 2\theta = \frac{1 - \tan^{2} \theta}{1 + \tan^{2} \theta}$

ব্যাখ্যা (Explanation):

Related Questions

৫. i. cos⁡2θ=cos⁡2θ−sin⁡2θ\cos 2\theta = \cos^{2} \theta - \sin^{2} \thetacos2θ=cos2θ−sin2θ ii. cos⁡2θ=1−tan⁡2θ1+tan⁡2θ\cos 2\theta = \frac{1 - \tan^{2} \theta}{1 + \tan^{2} \theta}cos2θ=1+tan2θ1−tan2θ​

ব্যাখ্যা (Explanation):

Related Questions

৫. i. $\cos 2\theta = \cos^{2} \theta - \sin^{2} \theta$ ii. $\cos 2\theta = \frac{1 - \tan^{2} \theta}{1 + \tan^{2} \theta}$