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若lim(x->0)f(x)=0,则当g(x)有界,必有lim(x->0)f(x)g(x)=0A.当g(x)有界,必有lim(x->0)f(x)g(x)=0B.当g(x)为任意函数时,都有lim(x->0)f(x)g(x)=0C.仅当g(x)在0点的极限存在时,才有lim(x->0)f(x)g(x)=0D.仅当g(x)为常数时,才有l

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若lim(x->0)f(x)=0,则当g(x)有界,必有lim(x->0)f(x)g(x)=0
A.当g(x)有界,必有lim(x->0)f(x)g(x)=0
B.当g(x)为任意函数时,都有lim(x->0)f(x)g(x)=0
C.仅当g(x)在0点的极限存在时,才有lim(x->0)f(x)g(x)=0
D.仅当g(x)为常数时,才有lim(x->0)f(x)g(x)=0
ACD都拿不准.
若lim(x->0)f(x)=0,则()
▼优质解答
答案和解析
Ans:A
A.当g(x)有界,必有lim(x->0)f(x)g(x)=0 是正确
C.仅当g(x)在0点的极限存在时,才有lim(x->0)f(x)g(x)=0:不一定
e.g
g(x) = 3 ,f(x) = x
lim(x->0)g(x) =3
lim(x->0)f(x) = 0
lim(x->0) f(x).g(x) = lim(x->0) 3x =0
D.仅当g(x)为常数时,才有lim(x->0)f(x)g(x)=0 :不一定
e.g g(x)= x^2 ,f(x) =x
lim(x->0)f(x) .g(x) = lim(x->0)x^3 =0