Question

Cho a,b,c thỏa mãn \(\frac{1}{a^2+2}+\frac{1}{b^2+2}+\frac{1}{c^2+2}=1\). TÍnh A = \(\frac{a^2}{a^2+2}+\frac{b^2}{b^2+2}+\frac{c^2}{c^2+2}\)

Answer 1

\(A+2=A+\frac{2}{a^2+2}+\frac{2}{b^2+2}+\frac{2}{c^2+2}\)

\(=\frac{a^2}{a^2+2}+\frac{2}{a^2+2}+\frac{b^2}{b^2+2}+\frac{2}{b^2+2}+\frac{c^2}{c^2+2}+\frac{2}{c^2+2}=3\)

\(\Rightarrow A=1\)