数学题目问一下
已知(y-z)(y-z)-4(z-x)(x-y)=0,说明x+z=2y.
要详细过程,最好有注解,赏分20。请慎重,不要乱回答。谢谢合作!
参考答案:(y-z)^2 - 4(z-x)(x-y)
= y^2 - 2yz + z^2 - 4(xz - zy - x^2 + xy)
= y^2 + 2yz + z^2 - 4(xz - x^2 + xy)
= (y + z)^2 - 4x(z - x + y)
= 0
令u = y + z,则:
u^2 - 4x(u - x)
= u^2 - 4xu + 4x^2
= (u - 2x)^2
= 0
所以:
u = 2x
即:
y + z = 2x
看来你的题目又写错了哦~