7x0.80[ln（0.60x5.50+1.50）-0.1x3.50]=？

更新时间2020-11-23 17:12:40

7×0.8×[㏑(0.6×5.5+1.5)-0.1×3.5]

=5.6×㏑4.8-5.6×0.35

=5.6㏑4.8-1.96

≈8.78-1.96

=6.82