Melody

921 Questions
34315 Answers

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Mathigon website

I just discovered a site called mathigon

https://mathigon.org/dashboard
read more ..

Melody Apr 2, 2022

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Reporting problems.

There are a number of people having problems at the moment.
If you lodge an error can you please give all relevant information that you can think of.
Where you are in the world - the city or the country - is often very important information. read more ..

Melody Mar 16, 2022

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How to make an empty rectangle in Latex

I just worked out how to make an empty box of various horizonal size easily in LaTex.
This is not a recommended method, but other methods that I have tried here have not worked.
This coding is really simple. Just put letters inside read more ..

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Melody Mar 15, 2022

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871

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HAPPY ANNIVERSARY CHRIS! (CPhill)

I just realized that you became a member here exactly 8 years ago today!

It has been great to have you here all that time

off-topic

Melody Mar 13, 2022

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WELCOME BACK CPHILL !

Melody Feb 11, 2022

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Very interesting question. No high level maths required.

This question was posted a couple of days ago.
https://web2.0calc.com/questions/geometry_73561

I think it is really interesting. It looks much more difficult than it really needs to be. read more ..

Melody Feb 1, 2022

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Members have a better experience. Their questions get more attention.

Almost everyone is posting as a guest.
If you post as a member your questions will have a far greater chance of a timely and helpful response.
If you are a genuine learner and interact with us, you will become known and answerers will do read more ..

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Melody Jan 9, 2022

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HAPPY BIRTHDAY CHRIS!

Melody Dec 20, 2021

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Some guidelines for question askers.

Please note:
1) Ask only one question per post.
2) When asking a question talk about what you have tried for yourself. Then people will take you more seriously and will be more able and willing to help.
3) If you get an answer read more ..

off-topic

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Melody Nov 4, 2021

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Remeniscing - a little historical humour.

I just found this old post that some of you, who have been around for a while, might find amusing.

https://web2.0calc.com/questions/look-at-the-new-leader-board

off-topic

Melody Oct 29, 2021

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1054-6500= 5446 BC

MelodyOct 9, 2013

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0

First multiply both sides by x^2
then divide both sides by 2
you will now have
0=x^3 - 216
the cube root of 216 is 6
0=x^3 - 6^3
This is a factorization that you are probably supposed to know
0= (x+6)(x^2-6x+36)
Can you finish it?

MelodyOct 9, 2013

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81 OVER 100 SECOND POWER DIVIDED BY 2

do you mean 81 / ((100^2) /2 )?

MelodyOct 9, 2013

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Do you mean find the cubed root of 240?

Just press the cubed root button then 240
On some calculators you will need to press the inv button first.

Is this what you wanted?

cube root of 240 = 6.214 (correct to 3 decimal places)

MelodyOct 9, 2013

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0

x+3y=-5
First you need to be able to recognise that it is a line
then
The easiest way to graph it is by working out 2 points
Graph them and then draw in the line
If you choose x=0 you get 3y=-5 so y=-5/3 (0,-5/3)
If you choose y=0 you get x=-5 (-5,0)

MelodyOct 9, 2013

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0

The absolute value of anything has to be positive
Therefore it is a nonsense question and there can be no answers.

MelodyOct 9, 2013

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I think I've got it

The speed of light is 299,792,458 metres per second
Blue light : 459 x 10 ^-9 metres/wavelength

frequency is measured in Hertz which is wavelengths per second
(m/s) divided by (m/wavelengths) gives (wavelengths per second) The metres cancel out.

So frequency
=wavelengths / sec
=speed of light / wavelength
=299,792,458 / (459 x 10 ^-9)
=6.5314261 x 10 ¹⁴ Hertz
=653,143 GHz (to the nearest GHz)

I'm pretty sure that this is correct.

MelodyOct 8, 2013

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Well, that depends, just how big is a big cupcake?

MelodyOct 8, 2013

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I won't do your question but I will do a similar one and you can copy the technique.

1362.98

There needs to be just one non zero number in front of the decimal point: 1.36298
I have moved the decimal point 3 places, so the power will be 3
If it is a little number, less than 1, then the power will be negative
But, this is a big number, more than 9 so the power will be positive, that is, +3
so the answer is
1362.98 = 1.36298 x 10^3

i hope this helps and that you learn from it.

MelodyOct 8, 2013

+118724

0

y=x squared is a concave up parabola with the vertex at the origin.
When you plus two you just raise every point up by 2. So the vertex moves up to (0,2)

MelodyOct 8, 2013