数学M/S Paper 2讨论专区

Olien

我问了老师，老师又问回我：去哪里找老师帮你改kerja kursus呢？
老师说的话模棱两可，不知道要表达什么,是可以还是不可以呢？
老师给我两个建议：
1. 转校（我不想转啊，很麻烦）
2. 自己写信或者打电话自己询问

peaceboy

回复 441# Olien


    就先打电话去问
如果可以的话你就自己去找老师
或则去mpm website 看有没有相关的资料

peaceboy

回复 441# Olien


    刚刚帮你看了
  Bagaimanakah pelaksanaan kerja kursus bagi calon yang mengambil mata pelajaran di luar pakej yang ditawarkan di sekolah?
  Calon yang mengambil mata pelajaran di luar pakej yang ditawarkan di sekolah dikehendaki menduduki kertas peperiksaan bertulis, iaitu Kertas 5 sebagai ganti Pentaksiran Berasaskan Sekolah. Sekiranya sesuatu mata pelajaran tidak menawarkan Kertas 5, maka calon itu dikehendaki melaksanakan kerja kursus seperti calon persendirian individu.

CityCheah

given that f(x)=一个equation ,然后叫你show that f'(x)>=0 for all values of x.
请问有人懂这类的问题怎么做吗？

Allmaths

CityCheah 发表于 11-8-2012 06:43 PM
given that f(x)=一个equation ,然后叫你show that f'(x)>=0 for all values of x.
请问有人懂这类的问题怎 ...

把题目写出来，方便大家做个讨论。。。

CityCheah

Allmaths 发表于 11-8-2012 08:42 PM
把题目写出来，方便大家做个讨论。。。

If f(x)=x-ln(1+x^2),show that f'(x) >= 0 for all values of x.

peaceboy

CityCheah 发表于 12-8-2012 12:30 AM
If f(x)=x-ln(1+x^2),show that f'(x) >= 0 for all values of x.

f'(x)= 1 - 2x/(1+x^2)
      = (1+x^2)/(1+x^2) -  2x/(1+x^2)
      = (x^2 - 2x +1)/ (1+x^2)
     = (x-1)^2 / (1+x^2)

since (x-1)^2 and 1+x^2 is always >= 0, therefore f'(x) is >=0

永遠愛著許瑋倫

peaceboy 发表于 12-8-2012 03:03 AM
f'(x)= 1 - 2x/(1+x^2)
      = (1+x^2)/(1+x^2) -  2x/(1+x^2)
      = (x^2 - 2x +1)/ (1+x^2)

大大，請指教一下

1.A force of magnitude 5N act along OA and a force of 3pN act along OB.The angle between OA and OB is 120`.The resultant force has magnitude of (7^(1/2))pN.calculate the possible values of p and determine the angle between the resultant force and OA.

2.Two force with magnitude pN and qN where p+q = 36N, act along OA and OB.The resultant force is 24N and is perpendicular to OB.calculate
(a)the value of p and q
(b)angle between OA and OB.

萬分感謝!

menglee90

永遠愛著許瑋倫 发表于 12-8-2012 10:50 PM
大大，請指教一下

1.A force of magnitude 5N act along OA and a force of 3pN act along OB.The ang ...

永遠愛著許瑋倫

謝謝menglee哥
請在指教多一題
A boat with the speed 4m/s in calm water cross a river from south to north where distance is 100m.A current from the west to east at speed of 1.5m/s.Find the direction in which the boat should be steered and the time taken to cross the river.
Ans: 337.98'  , 26.95s

perhapslove

The cubic function is one of the most frequency occurring functions. It is interesting to investigate some properties of a cubic function.

1. Consider a cubic function f(x):ax^3+b , where a and b are real number and a not equal to 0. The shape of the graph of the cubic function depends on the value on the values of a and b.

（a） Investigate the shape of the graph of the cubic function for various value of a for the case b=0. Identify the point of inflexion.

（b） Investigate the shape of the graph if both a and b have the same sign and if a and b have different signs. Identify the point of inflexion in each case.

（c) Investigate the points of intersection of the graphs of f and its tangents. What can u say abt the number of point of intersection.
帮帮忙~~~

姷婈蝶湘

perhapslove 发表于 31-8-2012 02:39 AM
The cubic function is one of the most frequency occurring functions. It is interesting to investig ...

1. Consider a cubic function f(x):ax^3+b , where a and b are real number and a not equal to 0. The shape of the graph of the cubic function depends on the value on the values of a and b.

（a） Investigate the shape of the graph of the cubic function for various value of a for the case b=0. Identify the point of inflexion.
做6個graph, 分別3個-a, 3個+a, 最好就是號碼相差很大, 可以看得出graph的形狀的變化 eg, -20, -5, -1/2, +1/2, +5, +20
（b） Investigate the shape of the graph if both a and b have the same sign and if a and b have different signs. Identify the point of inflexion in each case.
做4個graph 分別 +a+b, +a-b, -a+b, -a-b , a和b的號碼自己喜歡
（c) Investigate the points of intersection of the graphs of f and its tangents. What can u say abt the number of point of intersection.
做大概6個graph, 用回(1a)的equation 做也行, 使用differentiation 找出你用的equation的tangent的equation, 把graph畫上, 就會看到有points of intersection, 有些有2個, 有些有1個

minhui82

a census conducted in a SCHOOL shows that the total hours per week pupils spent watching  television has a mean of 16.87 hours and a standard deviation of 5 hours . if a random sample of 100 pupils is taken , find
a) the probability that the sample mean is within 3/4 hour than 17 hours

menglee

P(16.25 < x < 17.75) = P[(16.25-16.87)/(5/sqrt(100)) < z < (17.75-16.87)/(5/sqrt(100))] = ...

ystiang

4. The sale values (output quantity multiplied by price) for four types of product of a company at current price and 1998 price arc as follows:

(RM million)	Sale value at  current price			Sale value at 1998  price
Type of product	1998	2009	2010	2009	2010
A	50	120	175	100	125
B	10	30	24	25	20
C	40	40	50	20	20
D	20	50	90	40	60
Total	120	240	339	185	225

Calculate:

(a) the Laspeyres quantity index for the year 2010 by using 1998 as the base year, [2 marks]

(b) the Laspeyres quantity index for the year 2010 by using 2009 as the base year, [3 marks]

(c) the percentage change in the output quantity of the company from 2009 to 2010. [1 marks]

这题乃是STPM 2011 Maths S的第4题。

(a) 225/120 * 100 = 187.5

(b) 我真的完全没有头绪 >_<

kelfaru

The Star newspapers are sold at Varsity Mall. The number of newspapers sold each day follows a normal probability distribution with a mean of 200 copies and a standard deviation of 17 copies. How many copies of The Star newspapers should Varsity Mall order, so that it only runs out of newspaper on 20% of the days?

不是很明白问题要的东西~

kelfaru

这题也不是很懂要怎样做~~

peaceboy

kelfaru 发表于 25-6-2013 02:26 PM
这题也不是很懂要怎样做~~

你早两个学期问我可能我还记得
btw hypothesis testing 素 FMT 的

walrein_lim88

kelfaru 发表于 25-6-2013 02:26 PM
这题也不是很懂要怎样做~~

你是大学生吧？ 别放在这里扰乱中六生吧，中六没有学ANOVA的。
ANOVA是为了TEST 这三者的MEAN有没有一样。
所以，b) 95% confidence level, 也是alpha = 5%, 从F-table 找critical value (CV)就是了，打过CV就证明了其中一双是有different mean的。

kelfaru

walrein_lim88 发表于 25-6-2013 07:02 PM
你是大学生吧？  别放在这里扰乱中六生吧，中六没有学ANOVA的。
ANOVA是为了TEST 这三者的MEAN有没有 ...

问题是怎样找F Statistic???