(1)计算:|-3|-(12)-1+(π-3)0-2cos60°;(2)先化简,再求值:(nn-1-2n-1n-1)÷n-1n+2,其如n=-3

2025-08-09 16:38:51
推荐回答(1个)
回答1:

(十)原式=3-2+十-十=十;

(2)原式=

a-2a+十
a-十
?
a+2
a-十
=-
a+2
a-十

当a=3时,原式=-
-3+2
-3-十
=-
8