题目内容
计算:
(1)2sin30°+3tan30°+tan45°;
(2)cos245°+tan60°•cos30°.
(1)2sin30°+3tan30°+tan45°;
(2)cos245°+tan60°•cos30°.
考点:特殊角的三角函数值
专题:
分析:(1)直接将有关角的三角函数值代入求出即可;
(2)直接将有关角的三角函数值代入求出即可.
(2)直接将有关角的三角函数值代入求出即可.
解答:解:(1)2sin30°+3tan30°+tan45°
=2×
+3×
+1
=2+
;
(2)cos245°+tan60°•cos30°
=(
)2+
×
=
+
=2.
=2×
| 1 |
| 2 |
| ||
| 3 |
=2+
| 3 |
(2)cos245°+tan60°•cos30°
=(
| ||
| 2 |
| 3 |
| ||
| 2 |
=
| 1 |
| 2 |
| 3 |
| 2 |
=2.
点评:此题主要考查了特殊角的三角函数值,正确记忆相关数据是解题关键.
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