来自黄无忌的问题
配方:y=-2x^2+260x-6500
配方:y=-2x^2+260x-6500
1回答
2020-07-31 09:33
配方:y=-2x^2+260x-6500
配方:y=-2x^2+260x-6500
=-2(x²-130x)-6500
=-2(x²-130x+65²-65²)-6500
=-2(x-65)²+2*65²-6500
=-2(x-65)²+1950