（a+b／2ab²）³÷（a²-b²／ab²）²÷[1／2（a-b）]²
=(a+b)³/8(ab²)³x(ab²)²/(a+b)²(a-b)²x4/(a-b)²
=(a+b)/8ab²(a-b)²x4/(a-b)²
=(a+b)/2ab²
=(-1/2+2/3)/(-1/2x2x4/9)
=(1/6)/(-4/9)
=-3/8接着，求值，（不许骂我懒）刚刚没看到 已经求值了 祝学习进步，望采纳~~