已知函数f(x)可导,且对任何实数x,y满足:f(x+y)=e^xf(y)+e^yf(x)和f'(0)=e 证明:f'(x)=f(x)+e^(x+1)e^x*f(x)
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已知函数f(x)可导,且对任何实数x,y满足:f(x+y)=e^xf(y)+e^yf(x)和f''(0)=e证明:f''(x)=f(x)+e^(x+1)e^x*f(x)已知函数f(x)可导,且对任何实数x
已知函数f(x)可导,且对任何实数x,y满足:f(x+y)=e^xf(y)+e^yf(x)和f'(0)=e 证明:f'(x)=f(x)+e^(x+1)e^x*f(x)
已知函数f(x)可导,且对任何实数x,y满足:f(x+y)=e^xf(y)+e^yf(x)和f'(0)=e 证明:f'(x)=f(x)+e^(x+1)
e^x*f(x)
已知函数f(x)可导,且对任何实数x,y满足:f(x+y)=e^xf(y)+e^yf(x)和f'(0)=e 证明:f'(x)=f(x)+e^(x+1)e^x*f(x)
put x=y =0
f(0) = f(0) + f(0)
=>f(0) = 0
f'(x)= lim(y->0)[f(x+y) - f(x)]/y
= lim(y->0)[e^xf(y)+e^yf(x) - f(x)]/y
= e^x lim(y->0)[f(0+y)-f(0)]/y + f(x) lim(y->0)( e^y - 1)/y
= e^xf'(0) + f(x)
= e^(x+1) + f(x)
请把e^xf(y)写的清楚点,是相乘还是f(y)作为幂