x^2+()+y^2=()^2,x^2+()+9y^2=()^2
问题描述:
x^2+()+y^2=()^2,x^2+()+9y^2=()^2
答
x^2+(±2xy)+y^2=(x±y)^2,x^2+(±6xy)+9y^2=(x±3y)^2
x^2+()+y^2=()^2,x^2+()+9y^2=()^2
x^2+(±2xy)+y^2=(x±y)^2,x^2+(±6xy)+9y^2=(x±3y)^2