You are Here: Home >< Maths

# Vectors watch

1. Hello guys, I don't understand how to do this question really.

Question :
Attachment 618632

Now, I drew many diagrams and the most accurate to me looked like this one lol. I got the right answers using this diagram but I don't know if it's correct and if it is why is O at the position of the hexagon it is?

Attachment 618636

Also, why is OC = 2AB... that also makes no sense to me :/.
2. (Original post by Chittesh14)
Hello guys, I don't understand how to do this question really.

Question :

Now, I drew many diagrams and the most accurate to me looked like this one lol. I got the right answers using this diagram but I don't know if it's correct and if it is why is O at the position of the hexagon it is?

Also, why is OC = 2AB... that also makes no sense to me :/.
There is a lot of symmetry in a regular hexagon. One useful fact is that a regular hexagon can be divided into 6 equilateral triangles.

Try marking the centre of the hexagon then draw in these 6 triangles and you should end up with 12 lines on your diagram which all have equal length. Hopefully that will help you see why the longest diagonals of the hexagon e.g. OC are twice the length of the edges e.g. AB. Also, all these lines on the diagram will hopefully help with looking for the vector pathways.

It shouldn't matter which corner is your 'O'. Since the vector pathways will always be the same, you can mark 'O' on any of the corners.
3. An important fact here is that a regular hexagon can be thought of as 6 equilateral triangles, like this.

From this diagram, you should be able to see how to find the vectors, since if you can find one vector for each of the 3 sides of one of the triangles, you can add/subtract these vectors to find any direction from one point to another.
4. (Original post by notnek)
There is a lot of symmetry in a regular hexagon. One useful fact is that a regular hexagon can be divided into 6 equilateral triangles.

Try marking the centre of the hexagon then draw in these 6 triangles and you should end up with 12 lines on your diagram which all have equal length. Hopefully that will help you see why the longest diagonals of the hexagon e.g. OC are twice the length of the edges e.g. AB. Also, all these lines on the diagram will hopefully help with looking for the vector pathways.

It shouldn't matter which corner is your 'O'. Since the vector pathways will always be the same, you can mark 'O' on any of the corners.
Thanks! Yes, I just realised that as long as the order is correct, the position of O does not matter lol. That's what I was trying - equilateral triangles but I guess my diagram was inaccurate :/. Thank you so much !

Posted from TSR Mobile
5. (Original post by lizardlizard)
An important fact here is that a regular hexagon can be thought of as 6 equilateral triangles, like this.

From this diagram, you should be able to see how to find the vectors, since if you can find one vector for each of the 3 sides of one of the triangles, you can add/subtract these vectors to find any direction from one point to another.
Thanks buddy, I got the question right anyway lol I knew the part after that - one point to the other because it was simple vectors I was just stupid enough to not realise the equilateral triangles stuff -_-.

Thanks a lot !

Posted from TSR Mobile

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: February 10, 2017
Today on TSR

### Edexcel GCSE Maths Unofficial Markscheme

Find out how you've done here

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

## Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE