(cos 45°-sin 30°)/(cos 45°+sin 30°)希望步骤详细··
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 01:19:35
![(cos 45°-sin 30°)/(cos 45°+sin 30°)希望步骤详细··](/uploads/image/z/2758317-69-7.jpg?t=%EF%BC%88cos+45%C2%B0-sin+30%C2%B0%EF%BC%89%2F%EF%BC%88cos+45%C2%B0%2Bsin+30%C2%B0%EF%BC%89%E5%B8%8C%E6%9C%9B%E6%AD%A5%E9%AA%A4%E8%AF%A6%E7%BB%86%C2%B7%C2%B7)
(cos 45°-sin 30°)/(cos 45°+sin 30°)希望步骤详细··
(cos 45°-sin 30°)/(cos 45°+sin 30°)
希望步骤详细··
(cos 45°-sin 30°)/(cos 45°+sin 30°)希望步骤详细··
=(1/根号2-1/2)/(1/根号2+1/2) 【上下同乘以2】
=(根号2-1)/(根号2+1) 【上下同乘以(根号2-1)】
=(根号2-1)^2/(根号2^2-1^2)
=2-2*根号2+1
=3-2根号2
(cos 45°-sin 30°)/(cos 45°+sin30°)
=(√2/2—1/2)/(√2/2+1/2)
=(√2-1)^2
直接算不就行了
(cos 45°-sin 30°)/(cos 45°+sin 30°)希望步骤详细··
求证下列各恒等式:1.sin(30°+α)+cos(60°+α)=cosα1.sin(30°+α)+cos(60°+α)=cosα2.sin(α+β)sin(α-β)=sin²α-sin²β3.cos(α+β)cos(α-β)=cos²β-sin²α
cos 60°+sin 45°-tan 30°=?
cos tan sin 30° 45° 60°是多少
sin ²45° +cos²30°
sin(α+30°)-sin(α-30°)/cosα
sin^2 30°+cos()=1
[sin(45°+θ)]/[cos(45°-θ)]-[cos(θ+60°)]/[sin(θ+30°)]=?
求cos (α+30°)cosα+sin(α+30°)sinα的值
2cos 30°-2sin 60°·cos 45°
COS 60°/SIN 30°—LAN 45°+SIN²45°
sin(α+30°)-sin(α-30°)/cosα 的值为?
求值[sin(α+30°)-sin(α-30°)]/cosα
为什么根号3sinα+cosα=2sin(α+30°)
计算:⑴cos^2 30°+sin^2 30°-tan45° ⑵cos30°-sin°45/sin°60-Cos°45.务必要有计算过程!
sin(a+45°)sin(a+15°)+cos(a+45°)cos(a+15°)
cos(α+30°)cosα+sin(α+30°)sinα等于?
sin(α+30°)cosα+cos(α+30°)sinα=