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#151 Re: Dark Discussions at Cafe Infinity » Nelson Mandela » 2008-07-18 01:08:52

Born: 18 July 1918 10112.gif
Birthplace: Umtata, Transkei
Best Known As: The first black president of South Africa


Name at birth: Rolihlahla Mandela

Nelson Mandela spent 27 years as a political prisoner in South Africa before becoming the country's first black president. Mandela was a leading member of the African National Congress (ANC), which opposed South Africa's white minority government and its policy of racial separation, known as apartheid. The government outlawed the ANC in 1960. Mandela was captured and jailed in 1962, and in 1964 he was convicted of treason and sentenced to life in prison. Instead of disappearing from view, Mandela became a prison-bound martyr and worldwide symbol of resistance to racism. South African President F.W. de Klerk finally lifted the ban on the ANC and released Mandela in 1990. Mandela used his stature to help dismantle apartheid and form a new multi-racial democracy, and he and de Klerk shared the Nobel Peace Prize in 1993. Mandela was elected the country's president in 1994. He served until 1999, when he was succeeded by his deputy Thabo Mbeki. Mandela's autobiography, Long Walk to Freedom, was published in 1994.

Mandela says in Long Walk to Freedom that he was given the English name "Nelson" by his teacher on his first day at school... Mandela has been married three times: to the former Evelyn Mase from 1944 to 1957, to Winnie Madikizela from 1958 to 1996, and to Graca Machel since 1998... Mandela's wife Winnie became a powerful figure in her own right while Mandela was imprisoned; however, her entanglement in a series of scandals led to the couple's estrangement in 1992, her dismissal from his cabinet in 1995, and their official divorce in 1996.

#152 Help Me ! » walk up » 2008-07-17 20:15:12

tony123
Replies: 1

A man can walk up a moving "up" escalator in 1/2 minute.

He can walk down this moving "up" escalator in 1 and 1/2 minutes. If his walking pace is the same going up stairs as it is going down stairs,

how long would it take him to climb the escalator stairs if it was not moving?

How long would it take him to go up the moving escalator if he stood still?

#153 Help Me ! » What is the greatest number » 2008-07-17 11:18:42

tony123
Replies: 7

What is the greatest number of parts the plane can be divided by:
n straight lines ?
n circles ?

#154 Puzzles and Games » Evaluate » 2008-07-17 06:09:48

tony123
Replies: 1

Evaluate

.

x------- 0

#156 Puzzles and Games » cyclic quadrilateral » 2008-07-15 22:20:44

tony123
Replies: 2

In a cyclic quadrilateral ABCD, prove that

#157 Puzzles and Games » k_n » 2008-07-15 20:55:07

tony123
Replies: 2

If

then prove that

#158 Exercises » In acute triangle ABC » 2008-07-08 09:57:27

tony123
Replies: 0

In acute triangle ABC with circumcenter O and altitude AP, angle C
is greater than or equal to angle B plus 30 degrees. Prove that angle A
plus angle COP is less than 90 degrees.

#159 Re: Puzzles and Games » Square » 2008-07-06 01:35:55

use[ ][/ ] , don t use [/ ] [/ ]

#160 Exercises » three distinct » 2008-07-06 00:37:47

tony123
Replies: 1

If a,b,c are three distinct nonzero real numbers and

for some real number t

prove that

.

#161 Re: Puzzles and Games » Square » 2008-07-05 07:00:02

im sory

a positive integer

#162 Puzzles and Games » Square » 2008-07-05 06:25:40

tony123
Replies: 10

prove that


is a Square
 

with

a positive integer

#163 Puzzles and Games » The value » 2008-07-03 21:41:30

tony123
Replies: 1

cos(a-b) + cos(b-c) + cos(c-a) = -3/2

The value (sina + sinb + sinc)/(cosa + cosb + cosc) is:
(i)Some Rational Number
(ii)Infinity
(iii)0
(iv)Indeterminate

#164 Puzzles and Games » f(n) » 2008-07-02 05:24:16

tony123
Replies: 1

Let

.
Find a simple general formula for f(n).

#165 Puzzles and Games » Solve in positive integers the cubic » 2008-07-01 23:51:02

tony123
Replies: 4

Solve in positive integers the cubic


x^3–(x+1)^2=2001

#166 Puzzles and Games » Evaluate the integral » 2008-07-01 01:59:46

tony123
Replies: 3

Evaluate the integral

from 0 to pi/2


∫ ln(sin x ) dx

#167 Puzzles and Games » A king » 2008-07-01 01:48:33

tony123
Replies: 1

A king was hungry one night and went downstairs to get some food ... He saw mangos in a dish and took 1/6 of them ... Then his wife went downstairs and got 1/5 of the remaining mangos ... Then his son came down and took 1/4 of the remaining mangos ... Then his oldest son went down and took 1/3 of the remaining mangos ... Last his youngest son came down and took 1/2 of the mangos left ... There are 3 mangos left ... How many mangos were in the dish at the beginning?

#168 Puzzles and Games » Compute Y Z/BD » 2008-06-29 09:45:57

tony123
Replies: 0

ABCD is a cyclic quadrilateral in which AB = 4,BC = 3,CD = 2, and AD = 5. Diagonals AC
and BD intersect at X. A circle ω passes through A and is tangent to BD at X. ω intersects AB and
AD at Y and Z respectively. Compute Y Z/BD.

#170 Puzzles and Games » Determine A. » 2008-06-05 21:35:49

tony123
Replies: 1

Let G = {M1, M2, ... , Mr} denote the set of n × n permutation matrices (those matrices which have only zeroes and ones as entries, and whose row and column sums are all one), and let A = (M1 + M2 + ... + Mr) / r denote the average of these matrices. Determine A.

#172 Puzzles and Games » Determine the number » 2008-06-05 05:51:03

tony123
Replies: 1

Determine the number of sections the plane is divided by the sides of a regular n-gon.

#173 Puzzles and Games » Solve the following equation » 2008-06-01 10:51:23

tony123
Replies: 1

Solve the following equation on the set of integers

#174 Puzzles and Games » For which » 2008-05-31 00:28:44

tony123
Replies: 1

For which positive integers n can n! be written as a difference of two squares

#175 Puzzles and Games » Two men » 2008-05-22 00:08:13

tony123
Replies: 1

Two men are walking towards each other along the side of a railway. A freight train overtakes one of them in 20 seconds, i.e., it takes 20 seconds for the train, engine to caboose, to pass him. Exactly 10 minutes after just reaching the first man, the train meets the other man coming in the opposite direction. The train passes this man in 18 seconds. How long after the train has passed the second man will the two men meet?

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