> 数学 >
2sin50°+cos10°(1+
3
tan10°)
1+cos10°
=______.
人气:276 ℃ 时间:2020-03-25 05:07:53
解答
原式=
2sin50°+cos10°•
cos10°+
3
sin10°
cos10°
2
cos5°
=
2sin50°+2sin40°
2
cos5°
=
2
2
sin(50°+45°)
2
cos5°
=
2
2
cos5°
2
cos5°
=2.
故答案为:2.
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版