教招数学极限试题及答案
一、单项选择题(每题2分,共10题)
1.当\(x\to0\)时,\(\sinx\)与\(x\)的关系是()
A.高阶无穷小B.低阶无穷小C.等价无穷小D.同阶但不等价无穷小
2.\(\lim_{x\to\infty}\frac{3x+1}{2x-1}\)的值为()
A.0B.\(\frac{3}{2}\)C.1D.\(\infty\)
3.若\(\lim_{x\toa}f(x)\)存在,则\(f(x)\)在\(x=a\)处()
A.一定有定义B.一定无定义C.不一定有定义D.以上都不对
4.函数\(f(x)=\frac{x^2-1}{x-1}\)在\(x\to1\)时的极限是()
A.1B.2C.0D.不存在
5.极限\(\lim_{x\to0}\frac{e^x-1}{x}\)的值为()
A.0B.1C.-1D.2
6.当\(x\to0\)时,\(1-\cosx\)是\(x^2\)的()
A.高阶无穷小B.低阶无穷小C.等价无穷小D.同阶但不等价无穷小
7.\(\lim_{x\to0}\frac{\sin3x}{x}\)的值为()
A.1B.3C.\(\frac{1}{3}\)D.0
8.若\(\lim_{x\tox_0}f(x)=A\),\(\lim_{x\tox_0}g(x)=B\),则\(\lim_{x\tox_0}[f(x)+g(x)]\)等于()
A.\(A-B\)B.\(A+B\)C.\(AB\)D.\(\frac{A}{B}\)(\(B\neq0\))
9.\(\lim_{n\to\infty}(1+\frac{1}{n})^{2n}\)的值为()
A.\(e\)B.\(e^2\)C.\(2e\)D.\(1\)
10.极限\(\lim_{x\to+\infty}\frac{\lnx}{x}\)的值为()
A.+\(\infty\)B.0C.1D.不存在
二、多项选择题(每题2分,共10题)
1.下列极限存在的是()
A.\(\lim_{x\to0}\frac{1}{x}\)B.\(\lim_{x\to0}\sinx\)C.\(\lim_{x\to\infty}\cosx\)D.\(\lim_{x\to0}e^x\)
2.当\(x\to0\)时,以下是无穷小量的有()
A.\(x^2\)B.\(\sinx\)C.\(\ln(1+x)\)D.\(e^x-1\)
3.极限运算法则中,若\(\lim_{x\tox_0}f(x)=A\),\(\lim_{x\tox_0}g(x)=B\),则正确的有()
A.\(\lim_{x\tox_0}[f(x)-g(x)]=A-B\)B.\(\lim_{x\tox_0}[f(x)g(x)]=AB\)
C.\(\lim_{x\tox_0}\frac{f(x)}{g(x)}=\frac{A}{B}\)(\(B\neq0\))D.\(\lim_{x\tox_0}[kf(x)]=kA\)(\(k\)为常数)
4.下列关于极限的说法正确的是()
A.数列极限是函数极限的特殊情况B.极限存在则函数在该点一定连续
C.无穷小量与有界函数的乘积是无穷小量D.两个无穷小量的商一定是无穷小量
5.当\(x\to\infty\)时,以下函数极限为0的有()
A.\(\frac{1}{x^2}\)B.\(\frac{\sinx}{x}\)C.\(e^{-x}\)D.\(\frac{1}{x+1}\)
6.以下与\(\lim_{x\to0}\frac{\sinx}{x}=1\)相关的极限有()
A.\(\lim_{x\to0}\frac{\sin2x}{2x}=1\)B.\(\lim_{x\to0}\frac{\tanx}{x}=1\)
C.\(\lim_{x\to0}\frac{\arcsinx}{x}=1\