设Fx,y)=f(x),f(x)在x0处连续，证明：对任意y0∈R，F(x,y)在(x0,y0)处连续 设fx（x，y）和 fy（x，y）在点（x0，y0）处连续，...
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\u518d\u5bf9y\u6c42\u504f\u5bfc\u5f970
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\u4e3a\u5e38\u6570 \u6240\u4ee5\u8fde\u7eed
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F(x,y)=f(x),f(x)在x0处连续.则F(x,y)在x0处连续，所以对任意y0∈R，F(x,y)在(x0,y0)处连续。『这是什么题目啊？晕！』对F（x，y）中的x求偏导得f‘（x0）
再对y求偏导得0
要求F（x，y）连续利用 可导必连续定理对其求x和y的偏导 得F’（x0，y0）=f‘（x0）+0
为常数 所以连续
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绛旓細F锛坸锛寉锛夊弻閲嶇Н鍒嗕负1 涓斿埄鐢ㄨ繕鍘熸硶 浠锛漷an锛坢锛塧bsm F锛坸锛寉锛=P(X<x,y =x鎴栬匶>=y)=1-P(X>=x锛-P锛圷> =y)+2P(X>=x锛塒锛圷> =y)-P(X>=x锛塒锛圷>=y) < =1-P(X>=x锛塒锛圷>=y) < =1-([1-P(X<x锛塢[1-p锛坹<y)] =x锛-P(X>=x锛塒锛圷>=y)>=...
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绛旓細璇佹槑锛歠(x)鍦≧涓婃弧瓒筹細f(x)=f'(x)锛宖(0)=1 璁緔=f(x)锛鍒檡=y'=dy/dx 鍒嗙鍙橀噺锛歞y /y =dx 绉垎锛歭ny=x-lnC 鎵浠ワ細y=f(x)=Ce^x 鍥犱负锛歠(0)=C=1 鎵浠ワ細f(x)=e^x
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绛旓細Fx(x) = 鈭f(x,y)*dy 姹傚崟鍙橀噺鐨勬湡鏈涳紝鍙互鍙傝冧互涓嬪叕寮忥細E(x) = 鈭玿*Fx(x)*dx=鈭埆x*f(x,y)*dxdy 璁撅紙X锛孻锛夋槸浜岀淮闅忔満鍙橀噺锛寈锛寉鏄换鎰忓疄鏁帮紝浜屽厓鍑芥暟锛F(x,y)=P({X鈮鈭℡鈮})=P(X鈮,Y鈮)锛岃绉颁簩缁撮殢鏈哄彉閲(X锛孻)鐨勫垎甯冨嚱鏁帮紝鎴栫О涓篨鍜孻鐨勮仈鍚堝垎甯冨嚱鏁般
