[sin(5π-α)cos(-π-α)]/[cos(α-π)cos(π/2+α)]化简

利用和差角公式化简 (2)sin(π/3+α)+sin(π/3-α)(2)sin(π/3+α)+sin(π/3-α)(3)cos(π/4+α)-cos(π/4-α)(4)cos(60°+α)+cos(60°-α)(5)sin(α-β)cosβ+cos(α-β)sinβ(6)cos(α+β)cosβ+sin(α+β)sinβ [sin(5π-α)cos(-π-α)]/[cos(α-π)cos(π/2+α)]化简 已知sinα+cosα=4/5且3π/22,若sinα+sinβ+sinγ=0,cosα+cosβ+cosγ=0,则cos(α-β)的值 化简sin(α-5π)/cos(3π-α)×cos(π/2-α)/sin(α-3π)×cos(8π-α)/sin(-α-4π) sin(α-β)sin(β-r)-cos(α-β)cos(r-β) 1.sin(α-β)sin(β-r)-cos(α-β)cos(r-β)2.（ tan4分之5π+tan12分之5π）/（1-tan12分之5π）3.[ sin（α+β）-2sinαcosβ]/2sinαsinβ+cos（α+β） 已知sin(3π+α)=2cos(α-4π)求cos(π/2 -α)+5sin(π/2 +α)/2cos(π+α)-sin(-α) 【三角函数】已知sin(α-π)=2cos(2π-α),求[sin(π-α）+5cos（2π-α)]/[3cos(π-α）-sin（-α)] 已知α∈（π,2π） sinα+cosα=1/5 求sinα*cosα sinα-cosα 若sin(α-π)=2cos(2π-α),求（sinα+5cosα）/（sinα-3cosα）的值, 已知sin a=2cos a 计算⑴（sinα+2cosα)/(5cosα-sinα) ⑵tan(α+π/4) 若cosα>sinα,(-π/2 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? 若(sinα+cosα)/(sinα-cosα)=2,求sin(α-5π)sin(3π/2-α)的值 已知sinα-cosα=-根号5/5,π sinα-cosα=-根号5/5,π 已知sinα-cosα=-√5/5 π 已知sinα-cosα=1/5,且π