sin(π/4-x)=5/13,则sin2x=?

sin(π/4-x)=5/13,则sin2x=? 已知sin(x+π/6)=1/4,求sin(5π/6-x)+sin^2(π/3-x) 2sin(x+π/4)sin(x-π/4)=? 已知sinα（x+π/6）=1/4,则sin（5π/6-x）+sin（π/3-x）的平方=? 已知sin(π/2-x)+sin(π-x)/cos(-x)+sin(2π-x)=2009,则tan(x+5π/4)等于?已知sin(π/2-x)+sin(π-x)/cos(-x)+sin(2π-x)=2009,则tan(x+5π/4)等于（） A.-2009 B.-1/2009 C.1/2009 D.2009 已知sin(π/4--x)=5/13,0 已知sin(π/4-x)=5/13,且0 sin(π/4-x)=3/5,则sin2x=? s = 2*sin(x)-sin(2*x)+2/3*sin(3*x)-1/2*sin(4*x)+2/5*sin(5*x)用matlab画图,求教啊 sin(x+π/4) 已知sin(x+π/4)=3/5,sin(x-π/4)=4/5 ,则tanx= 设sin(π/4-x)=5/13,则cos2x/cos(π/4+x)=_______ 设sin(π/4-x)=5/13,则cos2x/cos(π/4-x)=_______ 求证:(sin 2x /(1-cos 2x) )·(sin x /(1+sin x))=tan (π/4-x/2). 已知sin[a-b]cos a-cos[b-a]sin a=3/5,b是第三象限角,求sin[b+5π/4]的值第一题1/2cos x-√3/2sin x第二题√3sin x+cos x第三题√2[sin x-cos x]第四题√2cos x-√6sin x f(x)=（1+cotx)sin^2x-2sin(x+π/4)sin(x-π/4)还有一题, 已知函数f(x)=(1+1 anx)sin^2x+m sin(x+π/4)sin(x-π/4) 已知 sinα + cosα / sinα - cosα = 2 ,则 sin(α-5π) x sin(3π/2-α)等于A,3/4B,±3/10C,3/10D,-3/10