Question

prove that(a+b+c)³ -a³-b³-c³ =3 (a+b) (b+c) (c+a)
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Answer 1

Answer:

LHS

(a+b+c) ^3=a^3+b^3+c^3+3(a+b) (b+c) (c+a)

sub this

~~a^3+b^3+c^3+3(a+b) (b+c) (c+a) -a^3-b^3-c^3

~~3(a+b) (b+c) (c+a)

==RHS

Answer 2

Step-by-step explanation:

a3+b3+c3+ 3(a+b)(b+c)(c+a) - a3 -b3 -c3

=3(a+b) (b+c) (c+a)