Question

2. Ifà and ß be the zeros of x² + x + 1, then C² =(3
$\pi$
vh³+9v²)/h²

- is equal to:​

Answer 1

Step-by-step explanation:

Curved surface area of a cone , c = straight pirl

Volume of a cone , V = straight pir2h

L.H.S.= 3straight piVh3 - c2h2 + 9V2

= 3straight pih3  - (straight pirl)2h2 + 9  

= straight pi2r2h4 - straight pi2r2h2l2 + 9  

= straight pi2r2h4 - straight pi2r2h2(r2 + h2) + straight pi2r4h2 (Since, l2 = r2 + h2)

= straight pi2r2h4 - straight pi2r4h2 - straight pi2r2h4 + straight pi2r4h2 = 0 = R.H.S.