这道题的答案是？

maxinszz

k=6-(2/3)(3-2√3)^3=?

luyuanhong

6-(2/3)(3-2√3)^3

= 6-(2/3)[3^3-3×3^2×2√3+3×3×(2√3)^2-(2√3)^3]

= 6-(2/3)(27-54√3+108-24√3)

= 6-(2/3)(135-78√3)

= 6-(90-52√3)

= 52√3-84 ≈ 6.06664199

maxinszz

luyuanhong 发表于 2014-10-4 13:41
6-(2/3)(3-2√3)^3

= 6-(2/3)[3^3-3×3^2×2√3+3×3×(2√3)^2-(2√3)^3]

谢谢解答！