《中学数学杂志》(高中版 ) 2 0 0 4年第 5期《一个代数恒等式的诞生》一文中 ,宋庆先生通过类比赛题若 x,y∈ R,x +y =1,则xx2 +y3 +yx3 +y2 ≤ 83. (1)得到命题 1　若 x,y∈ R,x +y =1,则xx +y2 +yx2 +y≤ 43. (2 )并指出 ,完全类似地可证得命题 2　若 x,y∈ R,x +y =1,则yx In the article “The birth of an algebraic identity” in the “Middle School Mathematical Journal” (High School Edition), 2004, Issue No. 5, Mr. Song Qing passes the class competition if x, y ∈ R, x + y = 1, then xx2 + Y3 + yx3 + y2 ≤ 83. (1) Obtain the proposition 1 If x, y ∈ R, x + y =1, then xx + y2 + yx2 + y 43 43 (2) and point out that it is completely similarly verifiable Proposition 2 If x,y∈ R,x +y =1, then yx