MathIsimple
Back to Calculus

Calculus Practice Set 11

2 Hours

12 challenging problems

1Problem 1

Find limit: limn+[e(1+1n)n]n\lim_{n\to+\infty}\left[\frac{e}{\left(1+\frac{1}{n}\right)^n}\right]^n

2Problem 2

Find limit: limx0(1x21sin2x)\lim_{x\to 0}\left(\frac{1}{x^2}-\frac{1}{\sin^2 x}\right)

3Problem 3

Given function f(x)={x7+x2sin1x,x00,x=0f(x) = \begin{cases} \frac{x}{7}+x^2\sin\frac{1}{x} & ,x\neq 0 \\ 0 & ,x=0 \end{cases}

(1) Find f(0)f'(0); (2) Determine whether δ>0\exists\delta > 0 such that f(x)f(x) on (δ,δ)(-\delta,\delta) is strictly increasing.

4Problem 4

Known first derivative defined by curve formula y=y(x)y=y(x) can be written as 0x+yet2dt=0yusin[(u+1)2]du\int_0^{x+y}e^{-t^2}\,dt = \int_0^y u\sin[(u+1)^2]\,du, find y(0),y(0),y(0)y(0), y'(0), y''(0).

5Problem 5

Given function f(x)=e(1+xe)1tf(x) = e^{(1+\frac{x}{e})^{\frac{1}{t}}}, when x0x\to 0 has expansion f(x)=a0+a1x+a2x2+a3x3+a4x4+o(x4)f(x) = a_0+a_1x+a_2x^2+a_3x^3+a_4x^4+o(x^4), find a2,a3,a4a_2, a_3, a_4.

6Problem 6

Calculate improper integral: J=0+arctanexexdxJ = \int_0^{+\infty}\frac{\arctan e^x}{e^x}\,dx

7Problem 7

Known curve with polar equation r=2ar = 2^a, θ[e,π]\theta\in[e,\pi], find curve length.

8Problem 8

Calculate definite integral: I=0π4et2(costsint)costdtI = \int_0^{\frac{\pi}{4}}\frac{e^{\frac{t}{2}}(\cos t - \sin t)}{\sqrt{\cos t}}\,dt

9Problem 9

Given f(x)f(x) on x=x0x=x_0 continuous, limh0f(x0+h)+f(x0h)2f(x0)h2=f(x0)\lim_{h\to 0}\frac{f(x_0+h)+f(x_0-h)-2f(x_0)}{h^2} = f''(x_0).

10Problem 10

Given α\alpha is a positive integer, n=22023n = 2^{2023}, prove: For all 0<x<10 < x < 1, nαxneαnα1(lnx)αn^\alpha x^n \leq e^{-\alpha n^{\alpha-1}(-\ln x)^{-\alpha}}.

11Problem 11

Known f(x)f(x) and g(x)g(x) on [0,1][0,1] continuous, and for all x[0,1]x\in[0,1] there exists g(x)0g(x)\geq 0. Prove: There exists x0[0,1]\exists x_0\in[0,1] such that 01f(x)g(x)dx=f(x0)01g(x)dx\int_0^1f(x)g(x)\,dx = f(x_0)\int_0^1g(x)\,dx.

12Problem 12

Known f(x)f(x) on (1,2)(-1,2) continuous, on (1,2)(-1,2) except constant is differentiable. And g(x)g(x) on (1,2)(-1,2) is strictly increasing with constant above. Prove: There exists ξ(0,1)\exists\xi\in(0,1) such that 0ξf(x)g(x)dx=g(0)0ξf(x)dx+g(1)ξ1f(x)dx\int_0^\xi f(x)g(x)\,dx = g(0)\int_0^\xi f(x)\,dx + g(1)\int_\xi^1 f(x)\,dx.