sinΨ(x)=1-x²,Ψ(x)=arcsin(1-x²)为什么?怎么来的 已知f(x)=sinx,f[Ψ(x)]=1-x²,...
sin\u03a8(x)=1-x²\u7b49\u4e8e\u03a8(x)=arcsin(1-x²)?\u4e0d\u8be5\u662f\u03a8(x)=sin(1-x²)\u53cd\u51fd\u6570\u8fd9\u70b9\u5e38\u8bc6\u90fd\u4e0d\u4f1a\u5417\uff1f
sin\u03a8(x)=1-x²\u548c\u03a8(x)=sin(1-x²)\uff0c\u4e8c\u8005\u7b49\u4ef7\u5417\uff1f
\u5047\u5982\u662farcsin\u03a8(x)=1-x²\uff0c\u90a3\u4e48\u03a8(x)=sin(1-x²)\u5012\u662f\u6709\u53ef\u80fd\u3002\u56e0\u4e3aarcsin(sinx)=x
\u4f9b\u53c2\u8003\u3002
则ψ(x)=arcsin(1-x²);-1≦1-x²≦1,-2≦-x²≦0,即0≦x²≦2,-√2≦x≦√2。
绛旓細sin蟺x=sin(蟺-蟺x)x瓒嬩簬1鏃,蟺-蟺x瓒嬩簬闆,鍥犳x瓒嬩簬1鏃,sin(蟺-蟺x)绛変环浜幭-蟺x.
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绛旓細鍥炵瓟锛歽=sin²(1-x)=sin²(x-1) y'=2sin(x-1)*cos(x-1)
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绛旓細璇烽噰绾
绛旓細楂樹腑鐨勮瘽锛sinx锛弜 = sin(x-0)/(x-0) = limx->0 sin(x-0)/(x-0)鏍规嵁瀵兼暟鐨勫畾涔 杩欏氨鏄痵inx 鍦▁=0澶勭殑瀵兼暟 sin'x = cos x 鎵浠ュ綋x瓒嬪悜浜0锛宻inx锛弜=1 鏋侀檺鎬濇兂鐨勬濈淮鍔熻兘 鏋侀檺鎬濇兂鍦ㄧ幇浠f暟瀛︿箖鑷崇墿鐞嗗绛夊绉戜腑锛屾湁鐫骞挎硾鐨勫簲鐢紝杩欐槸鐢卞畠鏈韩鍥烘湁鐨勬濈淮鍔熻兘鎵鍐冲畾鐨勩傛瀬闄愭濇兂...
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绛旓細鍥犱负姝e鸡鍑芥暟sinX鐨勫彇鍊艰寖鍥存槸[-1锛1]鎵浠in²X鍙栧兼槸[0锛1]鎵浠1-sin²X鐨勫煎煙鏄痆0锛1]娉ㄦ剰鍖呮嫭0鍜1
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