题目计算:(1)(x−2y)2−x(x+2y)(1)\left(x-2y\right)^{2}-x\left(x+2y\right)(1)(x−2y)2−x(x+2y)；(2)2m+1m−(2−m)÷−m2+4m−4m2−4(2)\frac{2m+1}{m}-(2-m)÷\frac{-{m}^{2}+4m-4}{{m}^{2}-4}(2)m2m+1−(2−m)÷m2−4−m2+4m−4.知识点：分式的混合运算章节：数与式 / 分式
