sin(3∏-α)=-2sin(Π∕2+α)则sinαcosα等于
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/04 21:45:51
x)+0~ѯ{n=F@{:-x1HFͧ3B6&|m]}6IEi/0U65^dǮ{feԔ
-mJضe3jL1%PDM 7$ف< \
sin(3∏-α)=-2sin(Π∕2+α)则sinαcosα等于
①利用公式sin(π-θ)=sinθ和sin(∏+θ)=-sinθ证明:sin(-θ)=-sinθ②证明tanθsinθ∕tanθ-sinθ=1+cosθ∕sinθ③已知sinα-2cosα+1=0,α≠kπ+π∕2,k∈z求:tan(3π-α)和1∕sin2α-sinαcosα+1的值
化简sin(α+β)+sin(α-β)+2sinαsin(3π/2-β)=
2sin(α+π/3)=sinα+______
已知sin(2α+ β)=5sinβ,求证:2sin(α+ β)=3sinα
已知sin(3π-α)=-2sin(π/2+α)则sinαcosα
sinα+sinβ=1/3 求sinα-(cosβ)^2最大值
若(sinα+cosα)/(sinα-cosα)=2 则sin(α-5π)·sin(3π/2-α)=?
若sinα+cosα/sinα-cosα=2,则sin(α-5π)*sin(3π/2-α)等于?
傅里叶级数作图f(x)=2sin[x] - sin[2x] + 2/3sin[3x] - 1/2sin[4x]我用mathematica输入程序Plot[{2sin[x],-2sin[x],2sin[x] - sin[2x],-2sin[x] + sin[2x],2sin[x] - sin[2x] + 2/3sin[3x],-2sin[x] + sin[2x] - 2/3sin[3x],2sin[x] - sin[2x] + 2/3si
sin^3(-丌-α)=?sin^2(9∏/2+α)=?
化简:2sinα^2cosα-sin(3/2π-α)cos2α=
已知6sin²α+sinαcosα-2cos²α=0,α∈(π/2,π),求值1).(sinα-3cosα)/(sinα-cosα);2).sinαcosα-sin²α;3).sin²α-3cosαsinα-2
已知sinα 为锐角,且sinα ^2-sinα cosα -2cosα ^2=0.(1)求tanα 的值.(2)求sin(α -π∕3)
三角函数sin(2kπ+α)=sinα怎么用?sin(3π/2+α)=sin(2π-(π/2-α)=sin(-(π/2-α)=
已知sinα=4/5,求下列三角函数值1)sin(-α)2)sin(π-α)3)sin(π+α)4)sin(2π-α)
已知β∈[-π/6,π/4),且3(sinα)^2-2(sinβ)^2=2sinα,求(sinβ)^2-1/2sinα的最小值
设角a=-35π/6,则2sin(π+α)cos(π-α)-cos(π+α)/ 1+sin^2α+sin(π-α)-cos^2(π+α)sina=sin(-35π/6)=sin(-6π+π/6)=1/2 cosα=根号3/22sin(π+α)cos(π-α)-cos(π+α)/ [1+sin^2α+sin(π-α)-cos^2(π+α)]=2(-sinα)(-cosα)+cosα/[1+sin²