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Non-repeating decimals 2018-12-28
From Grace:
What is non repeating decimal
Answered by Penny Nom.
The square root of 6 is irrational 2017-10-02
From John:
In the initial assumption of that proof, root 6 is assumed to be a/b where a and b have no common factors, but why does having a common factor make it irrational?

Answered by Penny Nom.
Is the square root of 2 plus the square root of 2 irrational? 2017-03-29
From haya:
how can i prove the the square root of 2 plus the square root of 2 is an irrational number?
Answered by Penny Nom.
An example of an irrational number 2015-10-22
From Allison:
It ask me to find an example of an irrational number less than -5 and I don't understand what the difference from a rational number and an irrational number besides the fact that a rational number can be repeated and shown in a simple fraction and an irrational number can't be written in a simple fraction.
Can you help me?

Answered by Penny Nom.
2.236... 2015-10-13
From Ann:
What is the most specific category of numbers does this fall into? Rational or Irrational? Does the .... mean that it repeats?

Answered by Harley Weston.
Square roots 2015-09-21
From mariana:
I have read various articles on how to find the square root of irrational numbers and every article out there seems to be very confusing.
i read you answer to LUKOW about irrational numbers and i am still quite confused. Say i want to find the square root of 326. i know that it is between 18 and 19 because 18 is the square root of 324 and 19 is the square root of 361 im just very confused about the rest of the process. Please help! ( if possible i would appreciate two examples. thanks)

Answered by Penny Nom.
Is 22/7 is an irrational number? 2015-06-07
From Sayak:
Is 22/7 is an irrational number
Answered by Penny Nom.
1.2731568 2010-06-16
From angel:
is 1.2731568 a natural number a whole number a irrational number or a inter
Answered by Robert Dawson.
Proof that the root of 27 is irrational 2009-10-18
From Scarlet:
How do you prove that the square root of 27 is irrational?
Answered by Victoria West.
root 2 is irrational 2009-07-31
From prateet:
prove that root2 is an irrational number.
Answered by Robert Dawson.
Non-terminating, non-repeating decimals 2008-08-03
From Peter:
How do you take a random, non-terminating, non-repeating decimal into a fraction?
Answered by Stephen La Rocque.
How can the distance between two points be irrational? 2008-05-07
From Dawn:
Yesterday my advanced 7th grade pre-algebra students were finding the distance between two points on a coordinate grid using the distance formula. A student asked me how come we or math I guess is able to represent a finite distance with an irrational number. I found this to be a very interesting question. I and the 7 other math teachers on my staff had discussed this and we have a variety of thing to say to the kid, but nothing that amounts to an actual answer. The students have studied what it means for a number to be irrational, and they cannot understand how that can "measure" a line that obviously stops. Got any suggestions?
Answered by Stephen La Rocque, Penny Nom, Claude Tardif and Victoria West.
Is this an irrational number? 2008-03-22
From Tom:
Is it possible to build an irrational number with numbers that are just 1's and 2's where only finitely many 2's appear? If so, how do we build it and how do we know it is irrational?
Answered by Penny Nom.
An irrational number 2007-10-29
From Clara:
Find an irrational number between 0.53 (with 53 as repeating) and 0.54 (with 54 repeating)

I changed each to 53/99 and 54/99 with 1/99 being the difference.

Please help me.

Answered by Stephen La Rocque, Penny Nom and Harley Weston.
Irrational functions 2007-10-01
From alicia:
i have a question about irrationals functions.
i have been using them quite some time now, but i wonder where they can be found in daily life?
i hope you can help me,

Answered by Harley Weston.
The irrationality of PI 2007-08-07
From Matthew:
I have what I like to think of as a rather interesting question that I can't explain confidently for the life of me. If we take a circle with a radius of 1 and we calculate the circumference, we can use 2 pi R. Doing this calculation results in a circumference of 6.28318530717~ which goes on forever. However, if you were to take a that same circle in the real world, say with radius 1cm and wrap a string around it, and then measure the string, you don't get 6.28~, you get something like 6.2, a much more finite distance. The length of the string is not an irrational number, like the math claims it to be.
Answered by Claude Tardiff and Stephen La Rocque.
Prove that square root of 3 is irrational. 2006-12-21
From Humera:
Prove that square root of 3 is irrational.
Answered by Stephen La Rocque.
Help me prove that the square root of 6 is irrational 2006-09-23
From Sylvia:
Could you please help me prove that the square root of 6 is irrational ?
Answered by Stephen La Rocque.
The square root of 2 2002-03-05
From Roger:
Does two (2) have a square root or do the numbers just keep going? Are there any other numbers that behave like two when it comes to extracting the square root?
Answered by Penny Nom.
Some irrational numbers 2001-07-03
From Kellie:
  1. Is it possible to write pi as a fraction?

  2. Is it possible to write the square root of 2 as a fraction.. Explain why?

Answered by Harley Weston.
Cube roots on a calculator 2001-03-24
From Will:
Hi my name is Will.I have a question about the calculator TI-83 Plus or the use of a scientific calculator. It is about using them to turn a cubed root to a decimal. When using that for a rational and irrational number. Rational numbers is a number that terminates or repeates. A irrational number goes on and on and uses ... (like pie). Like when you type the cube root of 8 it gives you 2, and that is a rational number. The squre root of 2 is 1.41421356... that is irrational. So why is it when you put the cube root of 16 in the calculator it says 2.5198421 that is rational it terminates at the ninth digit and my float is set for the tenth? But why when you do it by hand you get the 2 times the cube root of 2 and that is irrational? Why is that?
Answered by Judi McDonald.
The n-th place of pi 2001-02-27
From Andrew:
I have always wondered; is it possible to find the value of an irrational number, such as (phi) at it's nth decimal place???

You would plug the decimal place into the formula and the value would be given at the specified decimal place.

When we look at the expression { (sqr 5 + 1)/2 } we are in a sense visualising the number in it's entirety, so the formula may include elements of the above expression in some form.
Answered by Claude Tardif.

Rational Numbers 2000-09-14
From Josh Kuhar:
How can you tell a number is rational?
Answered by Harley Weston.
The square root of 3 2000-04-04
From Mr. William:
Prove that root 3 is irrational
Answered by Harley Weston.
Rationals, irrationals and integers 2000-03-14
From Erin McKeon:
Why does the letter J represent the set of integers, the letter Q represent a set of rational numbers and the letter P represent a set of irrational numbers? What do each of these letters stand for?
Answered by Harley Weston.
Pi 2000-02-22
From Shelley Collier:
Numbers that can be written in the form p/q where p and q are integers, (q not 0), are known as rational numbers. What you are missing is that p and q must be integers. The fact that Pi is irrational means that you can't have a circle with both the circumference and diameter being integers. In fact you can't even have the circumference and diameter both rational since the quotient of two rationals is again a rational.
Answered by Claude Tardif and Penny Nom.
Irrational algebraic functions 2000-02-21
From Bucky Cadena:
Here is the multipart problem:

Given f(x) = x-3* squareroot of x + 4

What does the f(x) intercept equal Find the two values for which f(x) = -5 Find the one value for which f(x) = -3

Answered by Harley Weston.
The square root of two is never supposed to end 1999-03-06
From a wondering student:
i am algebra II and am in the 9th grade. today we were talking about rational and irrational numbers. When we were talking about square roots my friend and i were talking and we thought of something. if you have a square with sides of length one then the diagonal of the square is the square root of 2. Now the square root of two is never supposed to end. But the diagonal of the square ends so therefore doesn't the square root of 2 end. our math teacher did not really answer our question because it was not in the lesson plan and not to many people would see where we were coming from. the answer is really bugging me and i would like to have your input.
Answered by Jack LeSage and Penny Nom.
Root 17 is Irrational 1999-01-21
From John Murdock:
If you could help me out with this I would appreciate it. Prove that the square root of 17 is irrational.
Answered by Harley Weston.
6.99999... = ? 1998-12-05
From Tom:
I have had a rather heated arguement with my students. Please settle this for me.

Solve <,>, =
6.99999... __ 7

Thank you.
Answered by Penny Nom.

Terminating decimals 1998-11-16
From Debra Karr:
A college student studying elementary education asked me a question that I could not think of the correct answer. How can you look at a fraction and tell if is a terminating or non terminating decimal?
Answered by Jack LeSage and Penny Nom.
Rational and Irrational Numbers 1998-09-19
From Ri:
I am trying to explain rational & irrational numbers to my niece who is grade 7 and am having difficulties. Could you please explain the difference between rational & irrational numbers.

Thank you
Answered by Penny Nom.

Rational Numbers 1998-09-05
From Kristin Mckenzie:
Iam a secondary student with a math question I don't know how to do.
This is the question:

Explain whether each decimal number represents a rational number.

(a) 0.16

(b) 0.12

(c) -3.125

(d) -0.27

(e) -0,212 112 111 2 ....

(f) 0. 457 92

If it wouldn't be a problem i would really appreciate it if you sent back the instructions on how to do the question.

My name is Kristin Mckenzie and my return e-mail is lexus1999@hotmail.com

Thank-you for you time
Answered by Jack LeSage and Harley Weston.

A proof that e is Irrational. 1997-04-30
From Peter Hall and Jenny:
We have a little mathematical problem... we need some help proving e is an irrational number!

We don't feel very confident in our formulas, so if You have the time to give us a little explanation we would be very grateful!!!
Answered by Doug Farenick and Penny Nom.

Repeating Decimals 1997-01-24
From Grant Reed:
Is there a way to tell that the repeating decimal for 1/17 has no more than 16 repeating digits?
Answered by Penny Nom.
Ses points de discontinuités est les irrationnelles 2002-01-08
From Un eleve:
Je voudrait montrer qu'il n'existe pas de fonction de R--->R tels que ses points de discontinuités est les irrationnelles, en utilisant la methode de "baire".
Answered by Claude Tardif.



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