x^3-y^3 =(x-y)(x^2+yx+y^2)————① =(x-y){(x+1/2y)^2+3/4y^2————②这个式子是怎样从开始变形到第①步,又怎样变形到第②步,参考书上这样写的我看不懂,最好有语言叙述,
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![x^3-y^3 =(x-y)(x^2+yx+y^2)————① =(x-y){(x+1/2y)^2+3/4y^2————②这个式子是怎样从开始变形到第①步,又怎样变形到第②步,参考书上这样写的我看不懂,最好有语言叙述,](/uploads/image/z/12539746-10-6.jpg?t=x%5E3-y%5E3+%3D%28x-y%29%EF%BC%88x%5E2%2Byx%2By%5E2%29%E2%80%94%E2%80%94%E2%80%94%E2%80%94%E2%91%A0+%3D%28x-y%29%7B%28x%2B1%2F2y%29%5E2%2B3%2F4y%5E2%E2%80%94%E2%80%94%E2%80%94%E2%80%94%E2%91%A1%E8%BF%99%E4%B8%AA%E5%BC%8F%E5%AD%90%E6%98%AF%E6%80%8E%E6%A0%B7%E4%BB%8E%E5%BC%80%E5%A7%8B%E5%8F%98%E5%BD%A2%E5%88%B0%E7%AC%AC%E2%91%A0%E6%AD%A5%2C%E5%8F%88%E6%80%8E%E6%A0%B7%E5%8F%98%E5%BD%A2%E5%88%B0%E7%AC%AC%E2%91%A1%E6%AD%A5%2C%E5%8F%82%E8%80%83%E4%B9%A6%E4%B8%8A%E8%BF%99%E6%A0%B7%E5%86%99%E7%9A%84%E6%88%91%E7%9C%8B%E4%B8%8D%E6%87%82%2C%E6%9C%80%E5%A5%BD%E6%9C%89%E8%AF%AD%E8%A8%80%E5%8F%99%E8%BF%B0%2C)
x^3-y^3 =(x-y)(x^2+yx+y^2)————① =(x-y){(x+1/2y)^2+3/4y^2————②这个式子是怎样从开始变形到第①步,又怎样变形到第②步,参考书上这样写的我看不懂,最好有语言叙述,
x^3-y^3 =(x-y)(x^2+yx+y^2)————① =(x-y){(x+1/2y)^2+3/4y^2————②
这个式子是怎样从开始变形到第①步,又怎样变形到第②步,参考书上这样写的我看不懂,最好有语言叙述,
x^3-y^3 =(x-y)(x^2+yx+y^2)————① =(x-y){(x+1/2y)^2+3/4y^2————②这个式子是怎样从开始变形到第①步,又怎样变形到第②步,参考书上这样写的我看不懂,最好有语言叙述,
其实第一步就是立方差的公式,你记住就可以了.(x^3+y^3==(x+y)(x^2-yx+y^2)是立方和的公式).而第二步就是括号里运用配方的方法就可以得到了.
蛮简单的.
而且高中学习里面很少用到第二步的公式,最多用到配方的方法.
所以嘛,记住第一步就可以了.我也是高考刚考完,所以因该有点发言权吧~
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