y=1-cosx\sinx怎么化简成一种三角函数
sinx/(1-cosx)\u600e\u4e48\u5316\u7b80
\u7b54\uff1a\u4e8c\u500d\u89d2\u516c\u5f0f\uff1asin2a=2sinacosa\uff0ccos2a=2cos²a-1=1-2sin²asinx/(1-cosx)=2sin(x/2)cos(x/2)/[2sin²(x/2)]=cot(x/2)
=-\uff081-2sinx^2\uff09/2+sin2x/2+1+1/2
=sin2x/2-cos2x/2+3/2
=\u6839\u53f7sin(2x-\u03c0/4)+3/2
y=sin(x/2)\cos(x/2);
tan(x/2)=y;
vvxvxxv v
1-1/tanx
y=1-cotx
Y=1-COTX
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绛旓細x y 0 0 蟺/2 1 蟺 2 3蟺/2 1 2蟺 0
