(7) 分子分母同乘以 [√(1-x) + 3][4 - x^(1/3) + x^(2/3)]原式 = lim -(x+8)[4 - x^(1/3) + x^(2/3)]/{(8+x) [√(1-x) + 3]}= lim -[4 - x^(1/3) + x^(2/3)]/[√(1-x) + 3] = -10/6 = -5/3
