作业帮设角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
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![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](/uploads/image/z/1116671-23-1.jpg?t=%E8%AE%BE%E8%A7%92a%3D-35%CF%80%2F6%2C%E5%88%992sin%28%CF%80%2B%CE%B1%29cos%28%CF%80-%CE%B1%29-cos%28%CF%80%2B%CE%B1%29%2F+1%2Bsin%5E2%CE%B1%2Bsin%28%CF%80-%CE%B1%29-cos%5E2%28%CF%80%2B%CE%B1%29sina%3Dsin%28-35%CF%80%2F6%29%3Dsin%28-6%CF%80%2B%CF%80%2F6%29%3D1%2F2+cos%CE%B1%3D%E6%A0%B9%E5%8F%B73%2F22sin%28%CF%80%EF%BC%8B%CE%B1%29cos%28%CF%80-%CE%B1%29-cos%28%CF%80%2B%CE%B1%29%2F+%5B1%2Bsin%5E2%CE%B1%2Bsin%28%CF%80-%CE%B1%29-cos%5E2%28%CF%80%2B%CE%B1%29%5D%3D2%EF%BC%88-sin%CE%B1%29%28-cos%CE%B1%EF%BC%89%2Bcos%CE%B1%2F%5B1%2Bsin%26%23178%3B)
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
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3/2
2sin(π＋α)cos(π-α)-cos(π+α)/ [1+sin^2α+sin(π-α)-cos^2(π+α)]
=2（-sinα)(-cosα）+cosα/[1+sin²α+sinα-cos²α]
=2sinαcosα+cosα/[1+sin²α+sinα-cos²α]
接下来怎么算
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
慢慢算,一一分解