题目内容
求值:
(tan1°+tan2009°)+tan1°tan2009°=
| 3 |
1
1
.分析:运用公式tanα+tanβ=tan(α+β)(1-tanαtanβ)直接计算.
解答:解:
(tan1°+tan2009°)+tan1°tan2009°
=
tan2010°(1-tan1°tan2009°)+tan1°tan2009°
=
tan210°(1-tan1°tan2009°)+tan1°tan2009°
=
tan30°(1-tan1°tan2009°)+tan1°tan2009°
=1-tan1°tan2009°+tan1°tan2009°
=1.
故答案为:1.
| 3 |
=
| 3 |
=
| 3 |
=
| 3 |
=1-tan1°tan2009°+tan1°tan2009°
=1.
故答案为:1.
点评:本题考查诱导公式的应用,解题时要认真审题,注意公式tanα+tanβ=tan(α+β)(1-tanαtanβ)的灵活运用.
练习册系列答案
相关题目