Phi day?

[Prolix]

Dividing by zero is actually quite common in calculus. I suppose that is not quite true but taking the limit of an equation f(x) as x-> 0 comes pretty close. You would expect to see an asymptote there. Or have I been out of school too long?

[SerqFeht]

 

If you must... Here is another proof shamelessly ripped off from somewhere...

Step 1: -1/1 = 1/-1

Step 2: Taking the square root of both sides: sqrt(-1/1) = sqrt(1/-1) (where "sqrt" denotes the square-root symbol which cannot be displayed on text-only browsers.)

Step 3: Simplifying: sqrt(-1) / sqrt(1) = sqrt(1) / sqrt(-1)

Step 4: In other words, i/1 = 1/i.

Step 5: Therefore, i / 2 = 1 / (2i),

Step 6: i/2 + 3/(2i) = 1/(2i) + 3/(2i),

Step 7: i (i/2 + 3/(2i) ) = i ( 1/(2i) + 3/(2i) ),

Step 8: (i^2)/2 + (3i)/2i = i/(2i) + (3i)/(2i),

Step 9: (-1)/2 + 3/2 = 1/2 + 3/2,

Step 10: and this shows that 1=2.

There are more where that came from...

I hate math!!!

[Socius Rockus]

you can't sqrt a negative number..... That's something that's has been pounded into my head the last 4 years

[Prolix]

You can in a complex number system.

[hitancrias]

That last one is nice.

The error is in step three however.
sqrt(-1/1) does not equal sqrt(-1)/sqrt(1)

The general rule "sqrt(a/b) = sqrt(a) / sqrt(b)" is only true when a and b are positive real numbers.
I had to look that up though

[Prolix]

And I thought the real problem was that fractional numbers have a minus sign in front of the fraction instead of in the numerator or denominator. It is only when you get a variable as part of the fraction that the minus sign can be applied to it. Indeed, in that case, it is a shorthand for 0-x or -1*x, probably the latter. If the expression made sense it ought to similarly using decimal notation instead. The only time you would see the fractional form with the minus sign in the numerator or denominator and no variables would be in the process of simplification but never as the final result. Even with the variable you would rewrite it.

[neko kyouran]

http://www.youtube.com/watch?v=6cAs1YBELmA

 

Edit:

where "sqrt" denotes the square-root symbol which cannot be displayed on text-only browsers.

√2       

[Prolix]

He did specify text based browsers, neko. In the Links text based browser that looks like SQRT2. Then again, if your terminal is set for extended ascii you might be able to use ALT+251. √ =U+221A in unicode terms for sans font. Is that what you did neko or did you use an html entity: "&#8730", or "&radic". This forum does not seem to respect the full set of html entities.

[neko kyouran]

I learned many an alt code out of boredom whilst I waste my life away working for the man to get by.  It's the little things that get you by day by day.

[SerqFeht]

I used the magic of ctrl+c. It's pretty amazing. Who knew keyboards could do such a thing?