问题
解答题
计算cos245°+tan60°•cos30°-3tan230°+4sin230°
答案
原式=(
)2+2 2
×3
-3×3 2
+4×(3 3
)2=1 2
+1 2
-3 2
+13
=3-
.3
计算cos245°+tan60°•cos30°-3tan230°+4sin230°
原式=(
)2+2 2
×3
-3×3 2
+4×(3 3
)2=1 2
+1 2
-3 2
+13
=3-
.3