因式分解①、 ②.
计算: ( 1 3 ) - 1 + 18 + | - 2 | - 6 sin 45 °
( 1 )计算: 98 2 - 2 2 ;
( 2 )已知 a = - 12 . 8 , b = 2 . 8 ,求代数式 a 2 + 2 ab + b 2 的值.
计算: ( 2 - 3 ) ( 2 + 3 ) + tan 60 ° - ( π - 2 3 ) 0
( 1 )解方程: 2 x x + 3 = 1 x + 3 +1 ;
( 2 )解不等式组: 4 x + 2 > x - 7 3 ( x - 2 ) < 4 + x
( 1 )计算: 4 sin 60 ° ﹣ 12 + 3 - 1 0 ;
( 2 )化简 ( x + 1 ) ÷ ( 1 + 1 x ) .