Question

If a = 2, b = 3 and c = 4, find the value of ab+bc+ca+-a^2-b^2-c^2/3abc-a^3-b^3-c^3using a suitable identity.

Answer 1

Answer:

a3 + b3 + c3 - 3abc = (a + b + c)(a2 + b2 + c2 - ab - bc - ca)

Answer 2

Answer:

ab+bc+ac-a²-b²-c²/-a³-b³-c³+3abc

-a²-b²-c²+ab+BC+AC/-a³-b³-c³+3ab

-(a²+b²+c²-ab-bc-ac)/-(a³+b³+c³-3abc)

-(a²+b²+c²-ab-bc-ac)/-(a+b+c)(a²+b²+c²-ab-bc-ac)

-1/-a+b+c

=1/a+b+c

=1/2+3+4

=1/9