question if a+b+c=0 then prove that a cube+b cube +c cube-3abc=-25

Asked by vrishti TOKAS | 19th May, 2015, 12:35: PM

Expert Answer:

C o n s i d e r space t h e space i d e n t i t y a cubed plus b cubed plus c cubed minus 3 a b c equals open parentheses a plus b plus c close parentheses open parentheses a squared plus b squared plus c squared minus a b minus b c minus c a close parentheses G i v e n space t h a t space a plus b plus c equals 0. T h e r e f o r e comma a cubed plus b cubed plus c cubed minus 3 a b c equals 0 cross times open parentheses a squared plus b squared plus c squared minus a b minus b c minus c a close parentheses rightwards double arrow a cubed plus b cubed plus c cubed minus 3 a b c equals 0 rightwards double arrow a cubed plus b cubed plus c cubed equals 3 a b c K i n d l y space c h e c k space t h e space q u e s t i o n.

Answered by Vimala Ramamurthy | 20th May, 2015, 10:08: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.