(1)计算:|3?2|+20090?(?13)?1+3tan30°(2)先化简,再求值:12x?1x+y(x2?y2+x+y2x),其中x=2,y=3

2025-06-25 07:50:23
推荐回答(1个)
回答1:

(1)|

3
?2|+20090?(?
1
3
)?1+3tan30°
=2-
3
+1+3+
3

=6;
(2)
1
2x
?
1
x+y
(x2?y2+
x+y
2x
)

=
1
2x
-(x-y)-
1
2x

=-x+y,
把x=
2
,y=3代入,原式=-
2
+3.