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# Why is the gradient of the normal -1/m?

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1. (Original post by Zacken)
Yay! Glad it makes sense!
Thanks It's a new topic for me but I love it already. I don't mean to derail the thread but you do maths at uni, right?

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2. (Original post by Matrix123)
Thanks It's a new topic for me but I love it already. I don't mean to derail the thread but you do maths at uni, right?

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Nah, still an A-Level student, will hopefully be starting maths at Cambridge this October though, if all goes to plan. :-) You?
3. Here is a picture of the thing I described a few posts back
4. (Original post by Zacken)
Nah, still an A-Level student, will hopefully be starting maths at Cambridge this October though, if all goes to plan. :-) You?
I see, good luck with that Well, I've decided to do maths and further maths for A Levels as two of my subjects. As far as uni is concerned, I have no idea but maths is the most likely choice. I was just going to ask you how you were finding it if you were already at university

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5. (Original post by physicsmaths)
Do you understand upto the ax+by bit?

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(Original post by 16Characters....)
Are you familiar with the idea that if we have a line of gradient m then the angle it makes with the positive x-axis (i.e the x-axis moving rightwards) is ?
Both of your explanations are bizzare. Zacken explains it much better than you.

OP sketch:
y=5x
y=-.2x

on same graph, take some points and the idea will transpire evidently
6. (Original post by Matrix123)
I see, good luck with that Well, I've decided to do maths and further maths for A Levels as two of my subjects. As far as uni is concerned, I have no idea but maths is the most likely choice. I was just going to ask you how you were finding it if you were already at university

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I'll let you know next year.
7. (Original post by Zacken)
I'll let you know next year.
Oooh thank you

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8. (Original post by Pablo Picasso)
Both of your explanations are bizzare. Zacken explains it much better than you. ..
One person's illustration will suit some people better than others. This is free support and there is no need to be less than complimentary about someone's suggestion. It is like telling someone who asks a question that they are a bit dim.

Pablo's explanation (point!) is far from bizarre, it merely does not suit where you are coming from.
9. (Original post by Pablo Picasso)
Both of your explanations are bizzare. Zacken explains it much better than you.

OP sketch:
y=5x
y=-.2x

on same graph, take some points and the idea will transpire evidently
Take some points ain't explaining why.
You are just too dumb to understand my proof.
It is fairly easy if you know the dot product.
10. (Original post by Pablo Picasso)
Both of your explanations are bizzare. Zacken explains it much better than you.
I have four comments:
1) I provided no explanation, I was adding something to the argument of Argylerocksox who had said let the lines be y = xtan u and y = xtan(u + pi/2) without justification so I wanted to help the OP understand that argument.

2) I have not read through physicsmaths approach but there is nothing wrong with the trig approach, it proves the result and is easy if you know the pre-requisite knowledge.

3) Just because you do not like an argument does not mean that someone else does not. I personally do not like geometry hence the mostly symbolic trig approach is preferable for me. You may prefer the geometric approach but I and probably many others do not. The OP may fall into this category, or he may not. The fact is we do not know and there is no harm in alternate solutions to a question like this.

4) Tagging me and physicsmaths was not constructive in any way so I am not quite sure why you did it.
11. (Original post by 16Characters....)
I have four comments:
5) I didn't even explain anything...
12. Can someone tell me what "tagging" is? Is it a bad thing?

As in

"4) Tagging me and physicsmaths was not constructive in any way so I am not quite sure why you did it."
13. (Original post by nerak99)
Can someone tell me what "tagging" is? Is it a bad thing?

As in

"4) Tagging me and physicsmaths was not constructive in any way so I am not quite sure why you did it."
I used it in place of "quoting".
14. (Original post by 16Characters....)
I used it in place of "quoting".
Oh sorry. Thought it was my ignorance of Social Notworking

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