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extreme_machinations
May6-05, 11:31 AM
This Is Strange !!

Slope Of The Line X= 0[y- Axis] Is =+1
Slope Of The Line Y=0 [x-axis] Is= 0
Product Of The Slopes = 0

Now Product Of Two Perpendicular Lines Should Be = - 1

Is There A Contradiction ??

Zurtex
May6-05, 11:36 AM
It's funny how both the y-axis and the line y=x have the same gradient according to you :tongue:

extreme_machinations
May8-05, 09:22 AM
well ,
its even funnier how lack of reading skills can hamper a persons understanding .

if u pay attention sire ,u'll find that i said
that the line y=0 ,which you would agree is the x - axis and has a slope = 0

Zurtex
May8-05, 10:07 AM
well ,
its even funnier how lack of reading skills can hamper a persons understanding .

if u pay attention sire ,u'll find that i said
that the line y=0 ,which you would agree is the x - axis and has a slope = 0
I don't disagree with you, but do you know what the gradient of the line x=0 (the y-axis) is?

If you work that out you will understand where you went wrong. Please don't be so offended I was just lightly trying to point out your mistake.

honestrosewater
May8-05, 10:41 AM
This reminds me of the "proof" that 1 = 2. The mistake involved dividing by zero or something. ;)

HallsofIvy
May8-05, 07:13 PM
well ,
its even funnier how lack of reading skills can hamper a persons understanding .

if u pay attention sire ,u'll find that i said
that the line y=0 ,which you would agree is the x - axis and has a slope = 0

Good advice. You should take it yourself. Zurtex did not say anything about "the line y=0, which you would agree is the x-axis". He specifically referred to the "y-axis" and his point was that its slope is not 1!

James R
May8-05, 07:22 PM
The slope of the y axis (x=0) is infinite. And, as we all know, infinity times zero equals negative 1. :)

extreme_machinations
May9-05, 09:15 AM
oopsey !!
tan 45 syndrome !!!
sorry for that ,

but i thought anything multiplied by 0 is = 0
infinity multiplied by zero being -1 is brand new information to me ,can anyone tell me how this so ??

Zurtex
May9-05, 10:00 AM
oopsey !!
tan 45 syndrome !!!
sorry for that ,

but i thought anything multiplied by 0 is = 0
infinity multiplied by zero being -1 is brand new information to me ,can anyone tell me how this so ??
Infinity multiplied by 0 is not -1, heck it doesn't even make sense. But what you can do is work out the limit of the 2 sides when multiplied by each other, which goes something like this:

\lim_{x \rightarrow \infty} -x \frac{1}{x} = -1

Now although it's true that:

\lim_{x \rightarrow \infty} -x = -\infty

And:

\lim_{x \rightarrow \infty} \frac{1}{x} = 0

It only makes sense to say:

\lim_{x \rightarrow \infty} f(x) g(x) = \left( \lim_{x \rightarrow \infty} f(x) \right) \left( \lim_{x \rightarrow \infty} g(x) \right)

If f(x) and g(x) have limits as x approaches infinity. And as we see above -x has no limit as x approaches infinity.

James R
May9-05, 07:47 PM
Consider the following two lines:

Line A: y = -nx
Line B: y = x/n

The gradients of these two lines are:

Line A: gradient = -n
Line B: gradient = 1/n

Because any two lines which are perpendicular have gradients which multiply to give -1, we see immediately that line A is perpendicular to line B, for any given value of n.

Now, consider what happens in the limit as n goes to infinity. For line B we have:

\lim_{n \rightarrow \infty} y = \lim_{n \rightarrow \infty} x/n = 0

So, line B becomes the line y = 0.

We can write line A as:

x = -y/n

Taking the limit as n goes to infinity, we see that this line becomes the line x = 0.

Since we have taken the same limit in both cases, the lines A and B have remained perpendicular, and their gradients must still multiply to give -1. What we have, n terms of the gradients, is:

\lim_{n \rightarrow \infty} (-n)(1/n) = \lim_{n \rightarrow \infty} -1 = -1

extreme_machinations
May14-05, 08:34 AM
hey thats great conjecture !!

thanks

HallsofIvy
May14-05, 10:30 AM
hey thats great conjecture !!

thanks


What "conjecture" are you talking about? I didn't see any conjecture in this.

extreme_machinations
May15-05, 10:39 AM
I Was Just Using It In The General Sense ,not Strictly In The Mathematical Sense .

Please Ignore Whatever Does'nt Make Sense To You .

HallsofIvy
May15-05, 12:13 PM
What general sense then? I thought I knew what "conjecture" meant, even in general- and I don't see how it applies. Enlighten me.

extreme_machinations
May16-05, 09:31 AM
ok ,you win pal !!!!
im not gonna argue .
tell me what it was .

peace out ,