计算: 2 - 2 - 2 cos 60 ° + | - 12 | + ( π - 3 . 14 ) 0 .
(1)计算: ( - 2 ) 3 + ( 1 3 ) - 2 - 8 · sin 45 °
(2)分解因式: ( y + 2 x ) 2 - ( x + 2 y ) 2 .
(1)计算: ( - 3 ) 2 - ( 1 5 ) - 1 - 8 × 2 + ( - 2 ) 0
(2)先化简,再求值: 2 x 2 - 2 x x 2 - 1 - x x + 1 ,其中 x = - 2 .
解方程: 2 x x - 2 - 8 x 2 - 2 x = 1
计算: | 3 - 1 | - 2 × 6 + 1 2 - 3 - 8 2 3
先化简,再求值: ( 2 a a 2 - 1 - 1 a + 1 ) ÷ a + 2 a 2 - a ,其中 a = 5 .