已知集合A={x|(x-2)[x-(3a+1)]

问题描述:

已知集合A={x|(x-2)[x-(3a+1)]

先解B,x-4/x-5≤0,即x-4≥0 x-50,解得4≤x2,即a>1/3,(x-2)[x-(3a+1)]