All Answers 358108 Answers

That is excellent Chris. 

(2 + 1)! * 8  -  9 =

3! * 8 - 9

6 * 8 - 9 =

48 - 9  =

39

@@ End of Day Wrap      Sat 13/12/14       Sydney,   Australia         Time 11:10 pm          ♬

Hello everyone,

My goodness - this forum is growning!  Last year at this time there were hardly any questions at all.  And Kitty<3 and I were pretty much the only answerers.  How the forum has changed.  

Today and yesterday our wonderful answerers were Alan, Heureka, flflvm97, geno3141, Happy7, CPhill, TayJay, Zegroes, SelenaPubbiT, elldah14, Robey1Kanobi, newuser, Alexa4life, jlara1017, Mathematician, Saseflower, DannyMxyz, Sasini, Notats and jbows.  Thanks everyone.

There are many new people.  I strongly suggest that you look through the Sticky Post "Information for New People."  In particular please learn how to download images onto the forum.  It is not difficult. 

How to upload an Image.

Sun 14/12/14

1) Calculus, chain rule

Thanks you Alan, much appreciated.  

Apply Newton's 2nd law of motion (Force = mass*acceleration):

Vertical

Net force = -mg

-mg = m*d²y/dt²

so the mass cancels out and we are left with:

d²y/dt² = -g  which is the same as your equation Melody.

Horizontal

Net force = 0

0 = m*d²x/dt²

so dividing by the mass we are left with

d²x/dt² = 0

Mass is not relevant here.

.

Sometimes I copy them from here and paste them in but mostly i type them all.  :)

I usually work the problems out and code them straight in at the same time.

I often refer back to this thread to get the more complicated code that I want to use. 

This thread could really use cleaning up but for the moment it works for me. :)

I am not sue how many other people use it - not many I think.

LaTex is cool.  It is fun to learn, fun to use, and it makes the answers (and questions) easier to read and easier to interprete. 

I was hoping you would discuss it a little more than that Alan.

Is there anything more that you can say - I mean, why is mass irrelevant?

If, by "twenties" you are referring to twenty-pence pieces, then, as there are 5 of them in £1, there are 9*5 = 45 in £9.

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The mass is not needed here.

.

Is there something wrong with the calc on the home page??

I don't think so   

Yes, since there are no brackets in the question anon answer is the correct one.

(I was just reading you mind - we get fo used to people not putting in necessary brackets)

Please learn from this post :))

How to upload an Image.

just add them and then divide by 2

e = 83 degrees  Alternate angles on parallel lines.

use angles at a point to find f

f=g  Alt angles parallel lines

Use angle sum of a pentagon to find the last angle.

NOW

Use this to upload pictures.  See if you can work it out and if you can't then ask for help. :)

How to upload an Image.

There is no picture - that is sad  

Maybe this will help

 How to upload an Image.

Saseflower,

to write r squared you can use this ^ symbol.  That means to the power of

$$r^2=$$    r^2

>>What is 81^3/4?

$$\textcolor[rgb]{1,0,0}{\mathbf{\dfrac{81^3}{4}\ =\ 81\ \times\ 81\ \times\ 81\ \div\ 4\ =\ 132860.25}}$$

Your question does not make any sense 

Heureka can you please explain how you got your answer -

I would like to know how to do diaphantine equations too  

This is an approximation jbow.

root 15 cannot be simplified 

Excellent answer jbow4  

You did not say if you were allowed to use the digits more than once.

Here is one answer

$$9^2-(8-1)(9-2-1)=39$$

 96 miles in 1 1/2 hours

this is

96/3 = 32 miles in a half hour

there are 5 half hours in 2 and a half hours

so distance = 32*5 = 160miles

What other info do you have?