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ayano.chan

8 years agoPosted 8 years ago. Direct link to ayano.chan's post “is there such a thing cal...”

is there such a thing called 'fake' numbers?

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(31 votes)

Stefen

8 years agoPosted 8 years ago. Direct link to Stefen's post “I suspect you mean "fake"...”

I suspect you mean "fake" in that there are other numbers that are "real".

As Mr. Mark pointed out, there are

**imaginary numbers**, but don't read anything into the name "imaginary", like that they are not useful because they are somehow "made-up". Imaginary numbers are super powerful and useful - they allow us to extend the 1 dimensional**real number**line into the two dimensional**complex number**plane, and with that we can solve problems that we can't with just the real numbers alone.Many disciplines use complex numbers, but perhaps the one that affects you, me, and pretty well everyone on a daily basis is electronic engineering. Without complex numbers, the quantum analysis of transistor development would not be possible, meaning pretty much every electronic device you own would not exist.

Now what we call the real numbers weren't always called the real numbers. Mathematicians only started to call them real when the concept of the imaginary number was introduced. At that time, most mathematicians poo-poo-ed the idea of the properties of these new numbers

*(the square root of negative one? Oh no-no-no-no-no!)*so they called them "imaginary" as an insult, and that they only worked with REAL numbers. Well, it did not take long before the merits of imaginary numbers became apparent, but sadly the name did not change. I think it is sad because now, when students first hear of and begin to learn how to use these numbers, a sort of barrier is made in the students mind because at some level they think that these abstract imaginationsbe more difficult - and since it is human nature to resist the difficult, shazzam! - the student**must***makes*it difficult in their own mind. Imaginary numbers are not at all difficult, just a wee bit different, so, when you get to them, worry not! Onward ho!(53 votes)

surinder khan

7 years agoPosted 7 years ago. Direct link to surinder khan's post “Is infinity rational or i...”

Is infinity rational or irrational?

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(19 votes)

Richard He

7 years agoPosted 7 years ago. Direct link to Richard He's post “Infinity is neither ratio...”

Infinity is neither rational nor irrational. Rather, it's an abstract concept that we use in math. It doesn't have a numerical value; it just represents something that is larger than any number. So while we can represent a rational number (like 100) or an irrational number like

*pi*, we cannot do the same for infinity. Thus, infinity can't be classified as either rational or irrational.(44 votes)

Ángel Venegas

7 years agoPosted 7 years ago. Direct link to Ángel Venegas's post “I can divide an irrationa...”

I can divide an irrational number by 1, that's going to give me the same number, why isn't it rational?

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(14 votes)

Tjeerd Soms

7 years agoPosted 7 years ago. Direct link to Tjeerd Soms's post “Because a rational number...”

Because a rational number is a number than can be expressed as the fraction of two integers, not just any two numbers. 1 is an integer, of course, but the irrational number you are dividing by one most surely isn't.

(Good question though..!)

(27 votes)

Dani Berger

6 years agoPosted 6 years ago. Direct link to Dani Berger's post “Can somebody please tell ...”

Can somebody please tell me a list of what can be a rational number? I feel I am sort of getting it, but I am still a bit rough in some parts.

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(8 votes)

Kim Seidel

6 years agoPosted 6 years ago. Direct link to Kim Seidel's post “Rational numbers are all ...”

Rational numbers are all numbers that can be written as the ratio (or fraction) of 2 integers. This is the basic definition of a rational number. Here are examples of rational numbers:

-- All integers. Numbers like 0, 1, 2, 3, 4, .. etc. And like -1, -2, -3, -4, ... etc.

-- All terminating decimals. For example: 0.25; 5.142; etc.

-- All repeating decimals. For example: 0.33333... where 3 repeats forever. Or 2.45454545... where the 45 repeats forever

-- All fractions where each number is an integer, like: 5/4; 42/113; etc.Hope this helps.

(28 votes)

Sophia Nyquist

8 years agoPosted 8 years ago. Direct link to Sophia Nyquist's post “Where do you get the 750 ...”

Where do you get the 750 and so on? How do you solve ratios an easier way that has fractions? What is the formula?

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(18 votes)

1140858

2 years agoPosted 2 years ago. Direct link to 1140858's post “I didn’t really understan...”

I didn’t really understand your question. If your looking for a way to identify rationals and irrationals: a rational number is a number that can be expressed as an integer by an integer. Any operation between irrational and rational will give an irrational number(unless the rational is zero). But don’t forget PEMDAS(Parentheses, Exponents, Multiplication/Division, Addition/Subtraction)

(4 votes)

Jellybean

a year agoPosted a year ago. Direct link to Jellybean's post “This makes absolutely no ...”

This makes absolutely no sense to me. Help me, somebody! Halp!

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(8 votes)

RainbowSprinkles🏳️🌈

a year agoPosted a year ago. Direct link to RainbowSprinkles🏳️🌈's post “OK, let's start from the ...”

OK, let's start from the beginning. :D

We're told that "an irrational number is a number that cannot be expressed as a ratio of two integers."

So what this means is,**it's a number that you can't express as a generic fraction with two integers**(whole numbers, including negative numbers and zero). Obviously, this means all rational numbers*can.*So we can say "0.5 is rational because we can express it as 1/2, and 3 is also rational because we can express it as 3/1."

But, to use the example from the video, pi can't be written as

*a/b*(with an and b being integers). In fact, when it's written as a decimal, it goes on and on with no pattern to it: 3.14159...That's the second way to determine if a number is rational or not:

**does the decimal**. All this means is "does it eventually stop" (like, say, 26.62986413*terminate*or*repeat*eventually*is*long but it does end) and "is there a pattern to the decimal" (like 9.191919... or 7.7777...)So, a number with a decimal that goes on forever randomly, it's irrational.

If you have a number where the decimal stops and/or repeats itself, then it's rational.I hope this helped! ^^

(18 votes)

Pianoman🎹

a year agoPosted a year ago. Direct link to Pianoman🎹's post “Just curious to know, wha...”

Just curious to know, what if you write the pi as pie over pie(pi/pi) like a fraction? Would it become a rational number then?!

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(9 votes)

RainbowSprinkles🏳️🌈

a year agoPosted a year ago. Direct link to RainbowSprinkles🏳️🌈's post “Late answer, but yes. Bec...”

Late answer, but yes. Because anything divided by itself is just 1 (which is, of course, a rational number.)

This applies no matter how messed-up and irrational your number is, anything divided by itself is 1.

^^ hope this helped! (Even though it’s late…)(11 votes)

Sam D

9 years agoPosted 9 years ago. Direct link to Sam D's post “Sal is saying √8/2 is irr...”

Sal is saying √8/2 is irrational but, if you divide 8 by 2 you get 4 and √4 = 2

So how's it an irrational number? Or is it a rule that you can't divide first?•

(8 votes)

rmeissner

9 years agoPosted 9 years ago. Direct link to rmeissner's post “Order of Operations (Pare...”

Order of Operations (Parentheses, Exponents, Multiplication/Division, Addition/Subtraction = PEMDAS) states you need to "take care of" exponents prior to dividing. So since √8 is the same as 8^(1/2) 8 has an exponent (other than 1) on it. You need to take care of that before you divide.

Hope that helps.

(14 votes)

19zreed

11 years agoPosted 11 years ago. Direct link to 19zreed's post “why do we need rational a...”

why do we need rational and irrational numbers for real?

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(5 votes)

cbruns

11 years agoPosted 11 years ago. Direct link to cbruns's post “Pi (3.14159...) is a ver...”

Pi (3.14159...) is a very common irrational number. Pi is necessary to find areas of many shapes. Also, right triangles involve irrational numbers. Right triangles are important to make sure buildings are safe, cars protect their occupants in crashes, and people can travel great distances.

(9 votes)

BookQueen13

10 months agoPosted 10 months ago. Direct link to BookQueen13's post “Does anyone have a simple...”

Does anyone have a simple explanation on how to figure out whether or not its rational or irrational. I'm having a hard time understanding. Thank you!

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(5 votes)

lauluali234

10 months agoPosted 10 months ago. Direct link to lauluali234's post “if it can be converted in...”

if it can be converted into a fraction, it is rational

(6 votes)