计算: - | - 1 | + 12 ⋅ cos 30 ∘ - - 1 2 - 2 + ( π - 3 . 14 ) .
计算: | - 8 | + ( - 2 ) 3 + tan 45 ∘ - 4 .
计算: | - 2 | + 4 cos 30 ∘ - 1 2 - 1 + 12 .
解方程: x 6 - 30 - x 4 = 5 .
计算: 4 - ( π - 2016 ) 0 + | 3 - 2 | + 2 sin 60 ∘ .
先化简,再求值: x x - 3 ⋅ x 2 - 9 - 3 x ,其中x=2.