函数f(x)的定义域是(0,正无穷大),当x>1时,f(x)扫码下载作业帮拍照答疑一拍即得
问题描述:
函数f(x)的定义域是(0,正无穷大),当x>1时,f(x)
扫码下载作业帮
拍照答疑一拍即得
答
f(x.y) = f(x)+f(y)
令y=1+r(r>0),则f(xy)=f(x+rx) = f(x)+f(1+r)