sinx＝2cosx 则sin^2x＋1＝?

(sin^x/sinx-cosx)-sinx+cosx/tan^2x-1 求证 sin^2x/(sinx-cosx)-(sinx+cosx)/tan^2 x-1=sinx+cosx cosx-sinx/1+sin^2x不定积分 求证sin^2x/sinx-cosx-(sinx+cosx)/(tan^2-1)=sinx+cosx谢谢GGJJ sinx＝2cosx 则sin^2x＋1＝? 化简[sin^2(x)]/(sinx-cosx)-(sinx+cosx)/[tan^2(x)-1]-sinx 3sinx-2cosx=0 (1)(cosx-sinx)/(cosx+sinx)+(cosx+sinx)/(cosx-sinx) (2)sin^2 x-2sinxcosx+4cos^2 x (1+Sinx+Cosx+SinxCosx)/(Sinx+Sin^2 x)怎么化简成(Cscx+1+Cotx+Cosx)/(1+Sinx)? 证明(1+secx+tanx)/(1+secx-tanx)=(1+sinx)/cosx左边=（cosx/cosx+1/cosx+sinx/cosx)/（cosx/cosx+1/cosx-sinx/cosx)=(cosx+1+sinx)/(cosx+1-sinx)=(cosx+1+sinx)^2/[(cosx+1+sinx)(cosx+1-sinx)]=(cos²x+sin²x+2*sinx*cosx+2*cosx+2*sinx+1)/(cos² 化简sin^4x/sinx-cosx - (sinx+cosx)cos^2x/tan^2x-1 化简(sin^2x/sinx-cosx) -(sinx +cosx/tan^2x-1) 若(sin^2x+4)/cosx+1=2 则（cosx+3）(sinx+1)= sinx+cosx/sinx-cosx=2 求sinx/cos^3x +cosx/sin^3x 证明:sin2x=2sinx*cosx为什么sin(x+x)=sinx*cosx+cosx*sinx? 已知sinx＝2cosx,则sin^2(x)+1等于 ∫sinx/(cosx-sin^2x)dx sinx+cosx/sinx-cosx=2 求sin^2x+2sinxcosx-1的值 已知sinx+cosx=1/5 求2sinx*cosx+2sin²x/1-tanx