Melody

Thank you Alan,

I still don't understand but it doesn't matter.  I don't understand anything much lately. 

Thank you for trying to explain.

@@ End of Day Wrap    Tues 24/2/15     Sydney, Australia   Time 12:35 am  (Really Wed morning)    ♪ ♫

Hi all,

Today's answerers:  Bertie, Geno3141, Alan, GenericUsernameHere, CPhill, Tetration, Anima, Badinage, saseflower and dogeminer.   Withour you there would be no forum.  Thank you so much. 

Oh, we missed saseflower's birthday.    

It was on the 12 Feb and Saseflower became a teenager. 

We all hope that you had a wonderful birthday Saseflower.       

Here is a gift just for you.    http://gyazo.com/2d3ad258c69afbd62592636d90a2822b

Interest posts:

25/2/15

this calc is not great for graphs  (it is great for other things)

I suggest that you use this site

You have said this before i think Alan but my answer is the same as Chris's and I have found the derivative as requested.

Can you give me an example of where my way would give a false answer? 

I am assuming that all valid answers that I find are good but that sometimes my answer might not be valid.

I'll see if I can answer my own question

$$\\y=\sqrt{x}-1\qquad y\ge -1,\;\; x\ge 0\\
my\; way\\
$inverse function$\\
x=\sqrt{y}-1\qquad x\ge -1,\;\;\;y\ge 0 \\
y=(x+1)^2\qquad x\ge -1,\;\;\;y\ge 0 \\$$

What is wrong with that?     How should I do it ??

Thanks Bertie :)

This post is in Hebrew. I am sorry but the translation does not make sense.

הודעה זו היא בעברית.

אני מצטער, אבל התרגום לא הגיוני.

$$\\\frac{1sek}{0.1528\;dollar}=\frac{x\;sek}{1\;dollar}\\\\
\frac{1}{0.1528}=x\\\\$$

$${\frac{{\mathtt{1}}}{{\mathtt{0.152\: \!8}}}} = {\frac{{\mathtt{1\,250}}}{{\mathtt{191}}}} = {\mathtt{6.544\: \!502\: \!617\: \!801\: \!047\: \!1}}$$

$1 =  6.54 sek

arc tan is the same as inverse tan  :)

Thanks Chris,

why does

infinty - infinity = infinity ?