化简: a 2 - 1 a 2 ÷ 1 a - 1 = .
已知 a 1 = t 1 + t , a 2 = 1 1 - a 1 , a 3 = 1 1 - a 2 , ⋯ , a n + 1 = 1 1 - a n
(n为正整数,且t≠0,1),则a2016= (用含有t的代数式表示).
化简: a a - 2 - 4 a 2 - 2 a ÷ a + 2 a .
下列运算正确的是 ( )
72 · 1 288 = 72 288 = ± 1 2
( a b 2 ) 3 = a b 5
( x - y + 4 xy x - y ) ( x + y + 2 xy - 2 y 2 y - x ) = ( x + y ) 2
3 c 2 8 ab ÷ - 15 a 2 c 4 ab = - 2 c 5 a
计算 x 2 + 4 x + 4 x + 2 ÷ x 2 + 2 x x - 2 - 1 .
计算:
(1) ( 2 m + 3 n ) 2 - ( 2 m + n ) ( 2 m - n ) ;
(2) x - y x ÷ ( x + y 2 - 2 xy x ) .
计算 ( a - 1 + 1 a + 1 ) ÷ a 2 + 2 a a + 1 .
(1);
(2).
化简: ( a 2 a - 1 - a - 1 ) ÷ 2 a a 2 - 1 .
化简:.
(1)化简:;
(2)解不等式组,并写出它的正整数解.
计算:.
(1)计算:
(2)化简:
化简 ( a - b 2 a ) ÷ a - b a 的结果是 ( )
a - b
a + b
1 a - b
1 a + b