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If $$a + b + c = 0$$, then a factor of the expression $$(a+b)^{3}+(b+c)^{3}+(c+a)^{3}$$ is
GivenΒ :Β $$a + b + c = 0$$
=> $$(a+b)=-c$$
Cubing both sides, =>Β $$(a+b)^3=(-c)^3$$
=> $$a^3+b^3+3ab(a+b)=-c^3$$
=> $$a^3+b^3+3ab(-c)=-c^3$$
=> $$a^3+b^3+c^3=3abc$$ --------------(i)
Expression :Β $$(a+b)^{3}+(b+c)^{3}+(c+a)^{3}$$
= $$[a^3+b^3+3ab(a+b)]+[b^3+c^3+3bc(b+c)]+[c^3+a^3+3ca(c+a)]$$
=Β $$[a^3+b^3+3ab(-c)]+[b^3+c^3+3bc(-a)]+[c^3+a^3+3ca(-b)]$$
= $$2(a^3+b^3+c^3)-9abc$$
Substituting value from equation (i), we get :
= $$2(3abc)-9abc=-3abc$$
$$\therefore$$ $$abc$$ is a factor of the given expression.
=> Ans - (A)
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