Chứng minh rằng: a^2/(b + c) + b^2/(c + a) + c^2/(a + b) ≤ 1/abc

1. Cmr: a^2/(b+c) + b^2/(c+a) + c^2/(a+b) =< 1/abc
( a, b, c > 0)
2. Cho a, b, c>0. Cmr
1/(a^3+b^3+abc) + 1/(b^3+c^3+abc) + 1/( c^3+a^3+abc) =< 1/abc