在解答数学问题时,有些题目貌似数据不足、条件不够。让人难以入手解决,思维不知不觉就陷入了一个预设的“黑箱”,不能自拔.事实上,要真正解决这类问题,我们应从整体的角度着力研究数量之间的联系,而不能一味去进行具体的计算和证明.只有这样,才能巧妙地避开“黑箱”,使问题得以解决.这正是“山重水复疑无路,柳暗花明又一村”.例1已知x2+2x+y2-6y+10=0,求(x+y)~2的值. In answering mathematics questions, some topics seem to have insufficient data and insufficient conditions. It is difficult for people to solve the problem and the mind is unknowingly plunged into a preset “black box” that cannot be extricated. In fact, to really solve this kind of problem, we should focus on the research on the connection between the quantity from the perspective of the whole. To do specific calculations and proofs, only in this way can we cleverly avoid the “black box” and solve the problem. This is exactly what “there is no doubt about the mountains and rivers, and there is no way out of the mountains”. Example 1 Known x2+2x+ Y2-6y+10=0, find the value of (x+y)~2.