计算:(1)tan30°sin60°+cos230°-sin245°tan45°;(2)14tan245°+1sin230°?3cos230°+tan45°cos

2025-03-02 00:30:23
推荐回答(1个)
回答1:

(1)原式=
3
3
×
3
2
+(
3
2
2-(
2
2
2×1,
=
1
2
+
3
4
-
1
2
=
3
4


(2)原式=
1
4
+
1
1
4
-3×(
3
2
2+1-1,
=
1
4
+4-
9
4
=2.