Question

Long answer type questions: (4x 5 )=20marks 023verify that xº+yº+zº-3xyz = (x + y + 2) [(x + y)2+(y - z)? +(2 - x)21.​

Answer 1

Step-by-step explanation:

We have, L.H.S.=x 3 +y 3 +z 3 −3xyz=(x+y+z)(x +y 2 +z 2 −xy−yz−zx) [by poynomial identity]= 21

(x+y+z)(2x 2 +2y 2 +2z 2

−2xy−2yz−2zx)= 21 [(x+y+z)(x−y) 2 +(y−z) 2 +(z−x) 2 ]