问题
解答题
计算 (1)2sin30°-3tan45°+4cos60° (2)6tan230°-
|
答案
(1)原式=2×
-3×1+4×1 2 1 2
=1-3+2
=0;
(2)原式=6×(
)2-3 3
×3
-2×3 2 2 2
=6×
-1 3
-3 2 2
=
-1 2
.2
计算 (1)2sin30°-3tan45°+4cos60° (2)6tan230°-
|
(1)原式=2×
-3×1+4×1 2 1 2
=1-3+2
=0;
(2)原式=6×(
)2-3 3
×3
-2×3 2 2 2
=6×
-1 3
-3 2 2
=
-1 2
.2