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Junior High School Geometry Online Course

Published by kenneth in Math on March 27th, 2012 | No Comments »

Nowadays, we would find our life easier because so many online courses like geometry online course that could teach you geometry without required us to physically attend geometry class at school. Actually, What we need is just a desktop with the fast internet connection then we could always jump to learn the online geometry course. It is not like few years back that we have to physically attend geometry class (imagine the time that we have to spend for attending the class and comeback home).

Now with this geometry online class, we have a chance to learn geometry lessons without leaving our home.

Below is the statement that I try to solve one of the geometry problem, even this is not one of the real online geometry courses, but my expectation is to help others to understand the blue print of the simple online geometry course.

Before we jump to the complex of the geometry problem, I would like to play one piano song for you and let your mind relax and it would be easier for you to absorb the geometry lessons as below :

Let’s Start :

There is a triangle with <A, <B, <C. Assume the “<” is angle. ¼<C more 12^o than (2x<A)-2^o. ½<A less 5^o than (1:<B)x2^o. 2<B more 6^o than <C-10^o. Then I ask you how much <A ? (The answer may use the fraction)

The answer:

First Equation:

¼<C=2<A-2^o

Instant result:

<C=8<A-8^o

Second Equation:

½<A = (1:<B)x2^o-5^o

Instant result:

<A=<B-2½^o

Third Equation:

2<B=<C-10^o+6^o

Instant result:

<B=½<C-2^o

Make substitution <C to make it <A!

Because<C=8<A-8^o, so the result is:

½<C-2^o=4<A-2^o(<B=½<C-2^o=4<A-2^o)

Now, we have three equation, just combine it! We already knew the triangle formula is the three angle, if we combine, the result will always 180^o, same like our <A,<B,<C, the formula is :

<A+<B+<C=180^o

Now, we come to counting again…

<A=<A , <B=4<A-2^o , <C=8<A-8^o

Combine them with the statement the result must 180^o

<A+4<A-2^o+8<A-8^o = 180^o

13<A-10^o = 180^o

<A = 14 8/13^o

Hopefully this simple geometry online course could provide any one to learn with a better understanding for the concepts of online geometry class. Through reading, geometry online lessons and the independent exploration would make the learner leave the online class with more complete understanding of geometry and be able to think in a geometrical world.

Good Luck.

Makes Your Live Easier By Learning Calculus

Published by kenneth in Math on February 25th, 2012 | No Comments »

The difference between an amateur and a professional is that as an amateur one is at liberty to study only those things one likes, but as a professional, you must also study what one does not like. Consequently there are parts of a mathematical education that will seem laborious to a student just as all those hours of winter running in the cold and rain will be unattractive, but essential to the aspiring Olympic athlete. If students asked why they needed to learn some of the more intricate and unexciting parts of calculus, I used to tell them this story, one that the Russian physicist George Gamow tells us in his quirky autobiography, My world line. It is about the remarkable experience of one of Gamow’s friends, a young physicist from Vladivostok called Igor Tamm, who went on to share the Nobel prize for physics in 1958 for his part in discovering and understanding what is now known as the “Cerenkov Effect”.

In the Russian revolutionary period, Tamm was a young professor teaching physics at the University of Odessa in the Ukraine. Food was in short supply in the city and so he made a trip to a nearby village, which was under the apparent control of the communists, in an attempt to trade some silver spoons for something more edible like chickens. Suddenly the village was captured by an anti communist bandit leader and his militia, armed with rifles and explosives. The bandits were suspicious of Tamm, who was dressed in city clothes, and took him to their leader, who demanded to know who he was and what he did. Tamm tried to explain that he was merely a university professor looking for food.

“what kind of professor ?” the bandit leader asked.

“I teach mathematics” Tamm replied.

“Mathematics ?” said the bandit. “All right! Then give me an estimate of the error one makes by cutting off Maclaurin’s series at the 9^th term. Do this and you will go free. If you fail, and you will be shot!”

Tamm was not a little astonished. At gunpoint, somewhat nervously, he managed to work out the answer to the problem : a tricky piece of mathematics that students are taught in their first course of calculus in a university degree course of mathematics. He showed it to the bandit leader, who perused it and declared “Correct ! Go home !”.

Tamm never discovered who that strange bandit leader was. He probably ended up in charge of university quality assurance somewhere.

Tags: Calculus, course, george gamow, igor tamm, mathematics, nobel prize for physics, physicist, physicist george, physics, student, village

Have Fun with Small Mind-reading Tricks

Published by kenneth in Science on February 2nd, 2012 | No Comments »

Sometimes learning math might give you some fun, especially for someone who love numbers. Math also can teach you small tricks like mind-reading.

Try to think of a number between 1 and 9. Then multiply it by number 9 and add the digits of this new number together. Then subtract 4 from your answer and you will be left with a single digit number. Next, try convert this number to a letter. If you number is 1 it becomes A, 2 becomes B, 3 becomes C, 4 becomes D, 5 becomes E, 6 becomes F and so on. Now think of a type of animal that begins with your chosen letter and imagine that animal as strongly as you can. Hold it vividly in the forefront of your mind. It’s an Elephant.

This is a very simple trick, and you ought to be able to work out how I was able to guess the animal of your choice with such a high likelihood of success. There is a little mathematics involved, in that some simple properties of numbers are exploited, but there is also a psychological and even zoological ingredient as well.

There is another trick of this general sort that involves only the properties of numbers. It uses the number 1089, which you may well already have listed among your favorites. It was the year in which there was an earthquake in England, it is also a perfect square (33 x 33); but its most striking property is the following.

Pick any 3 digit number in which the digits are all different (like 153), make a second number by reversing the order of the 3 digits (become 351). Now take the smaller of the two numbers away from the larger (351 – 153 = 198, if your number has only 2 digits, like 23 then put a 0 (zero) in front, so 023). Now add this to the number you get by writing it backwards (so 198 + 891 = 1089). Whatever number you chose at the outset, you will end up with 1089 after this sequence of operations.

Tags: Auto, digit, Draft, earthquake in england, Fun, Learning, learning math, letter, math, Mind-reading, perfect square, Small, striking property, Tricks

Learning Math is Fun and Easy

Published by kenneth in Math on January 10th, 2012 | No Comments »

$Math is fun and easy image$

$Math is fun and easy image$ Just come back from holiday after travelling to other cities for refreshing myself and my family. Now it’s come again for me to have a normal life as usually I did, like wake up at 6 AM, some courses that I have to take until 8 PM and having fun with friends.

I have spent 1 hour to post this small math problem to my blog.

Mostly students always feel bored when they are trying to learn math, especially when facing with numbers, degree and operations on math. Usually their mind will become down at first sight before they even try to solve that problem.

So, again I try to solve another math problem like below, hopefully can help for those who might need this :

1²+ 2²+ 3²+ … + 500²= …

How to do this with the simplest way?

Easy, just use this formula…

500 { 500 + 1 } { ( 2 x 500 ) + 1 } = 500 x 501 x 1001 = 250.750.500 = 41.791.750 6 6 6

Explanations :

Assume the last number equal to n.
Take n multiply { n + 1 } multiply { 2n + 1 } then divide it by 6

Should you have any comments, just do not hesitate to write it down below…….

Tags: Fun, fun with friends, having fun with friends, holiday, learn math, Learning, learning math, life, math problem

The Fast Way to Solve Math degree 3

Published by kenneth in Math on November 30th, 2011 | No Comments »

$math-image$

Hey Friends, Sometimes when we learn math, we feel bored and we think again and again but the number that comes out always 1, 2, 3, etc.

Even when we go to store, we always dealt with those numbers because we need to make the transaction at the cashier.

Now we come to the real math world again ! Try to solve math with my simplest way.

I have a question and fast way to answer this question !

1³ + 2³+ 3³ + … + 50³ = …

For solving this question , please see the following answer :

Easy…, just take last number , degree with 2 , divided by 4 , then multiply with ( Last number + 1 )².

50² : 4 ( 50 + 1 )² = 625 x 51² = 1.625.625.

That’s all I can do now , hope you come back again.

Feel free to post your comments.

Tags: Auto, degree, Draft, Hey, hey friends, math degree, math world, Solve, transaction, x 512

First Junior High School Math Competition : Mid November 2011

Published by kenneth in Math on November 13th, 2011 | 3 Comments »

Today I struggle with Math Competition. For sure I am flattered for getting this opportunity.

Few number of the questions in this Junior High School Math Competition, I try to figure it out as below :

1 + 2 + … + 99 + 100 + 99 + … + 2 + 1 = …
How to do this with fast way???
Just take the middle number and multiply the same number too.
100 x 100 = 10.000.
(1 – ½ ) ( 1 – ⅓ ) … ( 1 – 1 / 2012 )
How to do this with fast way???
Just take the last number : 1 / 2012.
745²– 255²= …
How to do this with fast way???
( 745 + 255 ) ( 745 – 255 ) = 490.000.

Another questions not in this Junior High School Math Competition that I found the simplest way to solve :

1 + 2 + … + 118 + 119 = …
How to do this with fast way???
{ ( 1 + 119 ) ( 119 : 2 ) } = 120 x 59,5 = 7140.
1 + 2 + … + 179 + 180 = …
How to do this with fast way???
( 180 + 1 ) ( 180 : 2 )
181 x 90 = 16.290.
11 + 22 + 33 + … =…
10 + 20 + 30 + …
How to do this with fast way???
Just take the first number : 11 / 10.