化简:cos^2θcotθ+sin^2θtanθ+2cosθsinθ

问题描述:

化简:cos^2θcotθ+sin^2θtanθ+2cosθsinθ

原式=cos^3θ/sinθ+sin^3θ/cosθ+2cosθsinθ=(cos^4θ+sin^4θ)/(sinθcosθ) +2cosθsinθ=(cos^4θ+sin^4θ+2cos²θsin²θ)/(sinθcosθ) =(cos²θ+sin²θ)²/(sinθcosθ) =1/(sinθc...