Question

verify that PQ + Q Cube + R cube minus 3 PQ is equal to 1 by 2 into P + Q + R into p minus Q whole square + Q - R whole square plus R minus P whole square​

Answer 1

Here is ur answer :

Let a = ( p - q)

b = ( q - r )

c = ( r - p )

a + b + c = p - q + q - r + r - p

( All the terms are cut)

Then, a + b + c = 0

Identity : If a + b + c = 0 then a³ + b³ + c³ = 3abc

( p - q )³ + ( q - r )³ + ( r - p )³

➡️ 3 ( p - q ) ( q - r ) ( r - p )

hope this answer helpful u