Question

Cho \(P=\dfrac{x}{y+z}+\dfrac{y}{z+x}+\dfrac{z}{x+y}\)

và \(Q=\dfrac{x^2}{y+z}+\dfrac{y^2}{z+x}+\dfrac{z^2}{x+y}\)

Chứng minh nếu P=1 thì Q=0

Answer 1

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Answer 2

1 câu đăng tận 3 lần thế b