计算或化简谢谢!求过程
来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/11/10 21:41:26
计算或化简谢谢!求过程
计算或化简
1.根号3cos30°+根号2sin45°
2.sin60°分之tan45°-cos60°×tan30°
3(sin60°+cos45°)(sin60°-cos45°) 谢谢
计算或化简
1.根号3cos30°+根号2sin45°
2.sin60°分之tan45°-cos60°×tan30°
3(sin60°+cos45°)(sin60°-cos45°) 谢谢
1.根号3cos30°+根号2sin45°
=√3*√3/2+√2*√2/2
=3/2+1
=5/2
2.sin60°分之tan45°-cos60°×tan30°
=1/(√3/2)-1/2*√3/3
=2√3/3-√3/6
=√3/2
3(sin60°+cos45°)(sin60°-cos45°)
=sin²60°-cos²45°
=(√3/2)²-(√2/2)²
=3/4-2/4
=1/4
=√3*√3/2+√2*√2/2
=3/2+1
=5/2
2.sin60°分之tan45°-cos60°×tan30°
=1/(√3/2)-1/2*√3/3
=2√3/3-√3/6
=√3/2
3(sin60°+cos45°)(sin60°-cos45°)
=sin²60°-cos²45°
=(√3/2)²-(√2/2)²
=3/4-2/4
=1/4