原式=2/5*[4*16/9-1]-1/3*（-8）=2/5*[64/9-1]+8/3=2/5*[64/9-9/9]+8/3=2/5*[55/9]+8/3=22/9+8/3=22/9+24/9=46/9
2/5*[4*(-4/3)^2-1]-1/3*(-2)^3 = 46/9
答案为 46/9
