(1)计算: tan 45 ° - ( 2 - 1 ) 0 + | - 5 |
(2)化简: 2 a - 1 a - 1 - a 2 - a ( a - 1 ) 2 .
计算:.
计算:
(1)计算(-10)3+;
计算(每题5分,共10分) (1) (2)(-5)2×-300÷5