Melody

921 Questions
34316 Answers

+1

1

1742

2

+118730

Mathigon website

I just discovered a site called mathigon

https://mathigon.org/dashboard
lire plus ..

Melody 2 avr. 2022

-8

610

1

+118730

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. lire plus ..

Melody 16 mars 2022

-2

8

1481

5

+118730

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 lire plus ..

●●●●●

Melody 15 mars 2022

-3

873

3

+118730

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

Hors sujet

Melody 13 mars 2022

-4

850

3

+118730

WELCOME BACK CPHILL !

Melody 11 févr. 2022

-5

719

2

+118730

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. lire plus ..

Melody 1 févr. 2022

-7

888

11

+118730

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 lire plus ..

●●●●●●●●●●●

Melody 9 janv. 2022

-6

1

997

3

+118730

HAPPY BIRTHDAY CHRIS!

Melody 20 déc. 2021

+5

16

5574

9

+118730

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 lire plus ..

Hors sujet

●●●●●●●●●

Melody 4 nov. 2021

-9

1093

1

+118730

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

Hors sujet

Melody 29 oct. 2021

+118730

0

Answer by 77E9VW

8(x-7)=-3 =>

8x - 56 = -3 =>

56 - 3 = 8x

56 = 8x

x = 56/8

x=6.625

77E9VW has made a little mistake. Can you find it?

Melody2 déc. 2013

+118730

0

how to find a domain of a combined function? example f(g(x)) do we have to consider the domain of both f and g?

I think so

I am going to experiment with a specific example.
g(x) = 1/x
from g(x) x cannot be 0

f(x) = 3/(x+2)
from f(x) x cannot be -2

f(g(x))= 3/ (1/x +2)
x can't be 0
1/x can't be -2 therefore x can't be -1/2
I don't think that x can be -2 either.

But what if i simplify first,
f(g(x))= 3/ (1/x +2)
f(g(x))= 3/ {(1+2x)/x}
f(g(x))= 3 * x/(1+2x)
now x can't be -1/2 (x=-2 or 0 would work here)

anyway, I think x cannot be -2, -1/2 or 0
I will get back to you on this one.

Melody2 déc. 2013

+118730

0

help please 3a squared +4ab

=3a*3a +4ab

=9a squares +4ab

Melody2 déc. 2013

+118730

0

f the density of a substance is equal to 2.5 g/mL and its mass is equal to 19 g, what is the volume of the substance?

Use the units to help you
ml/g * g cancels down to ml (the g cancel out)

2.5g/ml is equivalent to 1ml/2.5g

therefore
1ml/2.5g * 19g will give you the answer (in ml)

Melody2 déc. 2013

+118730

0

Hi Jedithious, it is nice to meet you.

I personally do not care how many you submit so long as they are proper questions.

I would like people to be more interactive with the replies sometimes, they would learn better that way.
and it is good to have interaction.

Melody.

Melody1 déc. 2013

+118730

0

A cylinder of radius 4cm and height 6cm is recast into a cone which has a base radius equals to the height of the cylinder.Find the total surface area of the cone.

This question is not complete.
You could ask what the height of the cone is if all the cylinder is recast into the cone (perpendicular height or slant height)
Or you could ask, how much of the material is reused if the height is such and such.
But to find the surface area of the cone, assuming that it is not identical to the cylinder, is not possible unless you are given a height.

The surface area of the cylinder is 292.53cm squared (correct to 2 decimal places)

Melody1 déc. 2013

+118730

0

And as for your elusive maths question - arn't you the clever one.

Melody1 déc. 2013

+118730

0

How would I simplify (1000^1/3)^1000^33.333...? I know it's too large a number to write in decimal notation, but how can it be written as 1000^x or 1000^1000^x?

(2^6)^4 = 2^6 * 2^6 * 2^6 * 2^6 = 2^24
hence
(2^a)^b = 2^(ab)
do you get where I am going here?

(2^6)^4^7 = 2^24^7 = 2^(24*7) or just 2^(6*4*7)

Now you can answer your own question,

Melody1 déc. 2013

+118730

0

91 is the answer

What is the procedure to solve a problem like this?
A number is palindromic, if it is the same backwards as forwards.
Of the largest palindrome made from the product of two two-digit numbers, find one of the numbers.
a) 92 b) 89 c) 90 d) 91
----------------------------------------------------------------------------

The biggest possible number is 99 times 92 = 9108
The first palindromic number less than 9108 is 9009
I tried 9009 divided by 89 and 9009 divided by 91
since 9009 is odd I knew the 2 even ones would not go into it

9009 divided by 91 = 99 exactly so
91 is the answer.

Melody1 déc. 2013

+118730

0

Multiply both sides by 5.6

Melody1 déc. 2013