作者rod24574575 (天然呆)
看板NTU-Exam
标题[试题] 99下 薛克民 微积分甲下 第三次小考
时间Sun May 1 20:17:32 2011
课程名称︰微积分甲下
课程性质︰必修
课程教师︰薛克民
开课学院:电资学院、工学院、管理学院
开课系所︰电机系、资工系、材料系、资管系
考试日期(年月日)︰100/4/11
考试时限(分钟):40分钟
是否需发放奖励金:是
(如未明确表示,则不予发放)
试题 :
˙每题十分
˙请详述计算过程,无计算过程的答案不予计分
1. Find the tangent, normal and curvature of the curve
γ(t) = ( cos(t) + t*sin(t) , sin(t) - t*cos(t) , t ). (10%)
2. At the point (1,3), a function f(x,y) has a derivative of -√5 in the
direction from (1,3) toward (2,1) and a derivative of √5 in the direction
from (1,3) toward (3,2). Find the directions in which the function f
increases most rapidly at (1,3), and find the rates of change in this
direction. (10%)
3. Determine whether the following limits exist. If it does, find the
value. (10%)
5x*√y
(a) lim ────────
(x,y)→(0,0) √(x^3 + y^3)
2 2 (x^2 + y^2)
x y e
(b) lim ─────────
(x,y)→(0,0) x^4 + y^4
4. Let u = u(x,y), where x = x(s,t) and y = y(s,t), and assume that all these
functions have continuous second derivatives. show that
2 2 2 2 2 2
δ u δ u ┌ δx ┐ δ u δx δy δ u ┌ δy ┐
─── = ───│ ──│ + 2 * ─── * ──* ── + ───│ ──│
δs^2 δx^2 └ δs ┘ δxδy δs δs δy^2 └ δs ┘
2 2
δu δ x δu δ y
+ ──* ─── + ──* ───
δx δs^2 δy δs^2
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 218.167.197.181
※ 编辑: rod24574575 来自: 218.167.197.181 (05/01 20:17)