乘法公式的运用:①x²+y²=(x+y)²-_____=(x-y)²+______.
问题描述:
乘法公式的运用:①x²+y²=(x+y)²-_____=(x-y)²+______.
②(x-y+z)(-x+y+z)=[z+(______)][z-(______)]=z²-(_____)²
答
①x²+y²=(x+y)²-2xy=(x-y)²+2xy
②(x-y+z)(-x+y+z)=[z+(x-y)][z-(x-y)]=z²-(x-y)²