作业帮cos75°*cos15°-sin225°*sin15°的值为?
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/05 05:02:22
cos75°*cos15°-sin225°*sin15°的值为?
cos75°*cos15°-sin225°*sin15°的值为?
cos75°*cos15°-sin225°*sin15°的值为?
cos75°*cos15°-sin225°*sin15°
= cos75°*cos15°- sin(180°+ 45°)*sin15°
= cos75°*cos15°+ sin45°*sin15°
= (√6-√2)/4 × (√6+√2)/4 + √2/2 × (√6-√2)/4
= (6-2)/16 + √2/2 × (√6-√2)/4
= 1/4 + √2/2 × (√6-√2)/4
= 1/4 + (√12-√4)/8
= 1/4 + (2√3-2)/8
= 1/4 + (√3-1)/4
= √3/4
cos75°*cos15°-sin225°*sin15°的值为?
cos75°cos15°-sin225°sin15°的值为应为cos75°cos15°-sin255°sin15°不好意思
cos15°cos75°=?
计算tan15°+cos15°/cos75°
cos75°-cos15°的值等于?
cos15°+cos75°怎么做
cos75°,cos15°分别得多少?
sin45°sin15°＋sin225°cos15°＝
(cos75°)^2+(cos15°)^2+cos75°cos15°=
cos75度cos15度—sin225度sin165度的值是多少?
sin165°cos75°+cos15°sin105°等于?
(tan75°-tan15°)cos75°cos15°
sin15°cos75°+cos15°sin105°=?
(cos15°-cos75°)(sin75°+sin15°)＝?
1sin15°cos75°+cos15°sin105°=?
sin15°cos75°+cos15°sin75°
cos15°cos30°cos60°cos75°=
cos15°cos45°－cos75°sin45°