化简sinx^2-cosxsinx
cosx)^2/[cosxsinx-(sinx)^2]\u5316\u7b80\u5206\u5b50\u5206\u6bcd\u540c\u65f6\u4e58\u4ee5\u4e00\u4e2acos\u5e73\u65b9x\uff0c\u5f97\u52301/tanx-tan\u5e73\u65b9x.
y=\u221a2*cos(x-45\u00b0\uff09+(1/2)*sin(2x)
两个公式sin(2x)＝2sin(x)cos(x)
cos(2x)＝1－2sin(x)^2
所以
sin(x)^2=[1-cos(2x)]/2
cos(x)sin(x)=sin(2x)/2
sin(x)^2-cos(x)sin(x)
=[1-cos(2x)]/2-sin(2x)/2
=[1-sin(2x)-cos(2x)]/2
=[1-根号2*sin(2x+45度)]/2
sinx^2=(1-cos2x)/2
绛旓細涓や釜鍏紡 sin(2x)锛2sin(x)cos(x)cos(2x)锛1锛2sin(x)^2 鎵浠 sin(x)^2=[1-cos(2x)]/2 cos(x)sin(x)=sin(2x)/2 sin(x)^2-cos(x)sin(x)=[1-cos(2x)]/2-sin(2x)/2 =[1-sin(2x)-cos(2x)]/2 =[1-鏍瑰彿2*sin(2x+45搴)]/2 ...
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