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odds and ends added 18/11/14

What does m divided by 3 minus 3 less than negative 6

Do you mean

What IS m divided by 3 minus 3 less than negative 6

it is

$$\\-6-[\frac{m}{3}-3]\\\\
=-6-\frac{m}{3}+3\\\\
=-6+3-\frac{m}{3}\\\\
-3-\frac{m}{3}\\\\$$

Just put it straight on the site calc as

6.5 *(1 – e^(-0.972/486))=

Yes I too have only the vaguest recollection of this stuff :))

It is the notation for permutation.

Say you have 7 books.  You want to randomly choose 3 of them and the order counts.  How many ways can those 3 books be chosen.

Mathematically this is "How many permutations of 3 books can I get from 7 books"

The answer is   $$^7P_3$$

you can do this on any scientific calculator.  On the web 2 calc on  the home page I could enter it as

nPr(7,3) and this is my answer ;    210

$${\left({\frac{{\mathtt{7}}{!}}{({\mathtt{7}}{\mathtt{\,-\,}}{\mathtt{3}}){!}}}\right)} = {\mathtt{210}}$$

I actually recall (kinda') that method from Linear Algebra........don't remember how to calculate that cross-product......maybe I'll go back and review it....

Hey.....I'm still working out how to write an equation of a line......!!!!

Well that is good - NOW we both have to 'get' Heureka's answer  LOL 

Look here 

OK, Melody...got it.....

Why do you want a space on a calculator for?

I am ready for this question - just let me think 

Ummmmm

If you have 2 eggs and one drop of what?   This is a trick question!   Open the door and let me out!!!  :)))

ok I redid it AGAIN. :)))))

If you still have questions just ask :))

Don't ask me....I'm about to learn why 2 + 2 = 4....

you have one egg

I've added some more dots but if you still want more let me know. :)))

I added it in my original explanation.

Well I thought I did but it does not appear to be there.

this is not my night for presentation.  LOL

I'll try again. :))

Thanks Heureka, that will give me plenty to think about :))

The first bit is almost correct  anon  

$$\\1000=500(1+0.03)^n\\
2=1.03^n\\
log2=log1.03^n\\
log2=nlog1.03\\
n=log2/log1.03$$

$${\frac{{log}_{10}\left({\mathtt{2}}\right)}{{log}_{10}\left({\mathtt{1.03}}\right)}} = {\mathtt{23.449\: \!772\: \!250\: \!437\: \!735\: \!9}}$$

It will be worth 1000 in 24 lots of 6 months = 12 years

I know this formula....but I don't see how you're getting this......can you "connect the dots" more fully for me??

Thanks

Sorry Chris that was on the Latex that i lost.

But here is the formula

Melody....how did you obtain the fraction    l 3x - 6 l / √13     as a perpendicular distance from R to PQ ????.....I'm not seeing how you got that

I just did a whole page of latex and lost the whole lot so now I will do a condensed version. 

Heureka, Your answer looks great but I don't understand it so I will do it my way.

Maybe you can explain your way?

Anyway here goes- again

Find the value of  x such that the area of a triangle whose vertices have coordinates

P(6, 5), Q(8, 2) and R( x, 11) is 15 square units.

distance PQ=sqrt(13)

Equation of line PQ is

3x+2y-28=0

Now I need the perp distance from R to PQ

a=3, b=2, c=-28, x1=x, y1=11

$$\\d=\frac{|3x+22-28|}{\sqrt{13}}\\\\
d=\frac{|3x-6|}{\sqrt{13}}\\\\
d=\frac{|3x-6|}{\sqrt{13}}\\\\$$

$$\\\mbox{perpendicular distance from R to PQ}=\frac{|3x-6|}{\sqrt{13}}\\\\
Area=\frac{1}{2}\times \sqrt{13} \times \frac{|3x-6|}{\sqrt{13}}\\\\
15=\frac{1}{2} \times |3x-6|\\\\
30=|3x-6|\\\\
30=3x-6\qquad or \qquad 30=6-3x\\\\
36=3x\qquad\qquad or \qquad 24=-3x\\\\
x=12\qquad\qquad \;\;or \qquad x=-8\\\\$$

Below are the 2 possible triangles.  :)

thank you all