# Vectors - GCSE Maths. What is a "Scalar Multiply"?

#1
I've been revisiting GCSE Vectors topic and I've come across a term called "scalar multiplies" according to my book this proves that two vectors are parallel to each other. It's not very clear and doesn't give an example of what a "scalar multiply" actually is. if someone could shine some light on this it would be much appreciated.
0
5 years ago
#2
(Original post by WarHammer-)
I've been revisiting GCSE Vectors topic and I've come across a term called "scalar multiplies" according to my book this proves that two vectors are parallel to each other. It's not very clear and doesn't give an example of what a "scalar multiply" actually is. if someone could shine some light on this it would be much appreciated.
The vector 6a+2b is a multiple of 3a+b, it is 2(3a+b). 6a+2b is therefore parallel to 3a+b.

Posted from TSR Mobile
0
5 years ago
#3
(Original post by gdunne42)
The vector 6a+2b is a multiple of 3a+b, it is 2(3a+b). 6a+2b is therefore parallel to 3a+b.

Posted from TSR Mobile
there ya go
1
#4
ah, thanks. that's really helpful. but does the multiply have to be a whole number?
0
5 years ago
#5
(Original post by WarHammer-)
ah, thanks. that's really helpful. but does the multiply have to be a whole number?
No it can be by any real number.
0
5 years ago
#6
(Original post by WarHammer-)
ah, thanks. that's really helpful. but does the multiply have to be a whole number?
No, As rdkgames has said, at GCSE level it could just as easily be a decimal or fractional multiple

Posted from TSR Mobile
0
#7
what if i have to prove that 2 or 3 vectors lie along a straight line, how would i go about doing this?
0
#8
i understand that scalar multiples are used again. but if a vector is a scalar multiple of another wouldn't this mean that the two are parallel? how does this relate to proving that the vectors lie in a straight line.
0
5 years ago
#9
(Original post by WarHammer-)
i understand that scalar multiples are used again. but if a vector is a scalar multiple of another wouldn't this mean that the two are parallel? how does this relate to proving that the vectors lie in a straight line.
If you show they are parallel and they start at (or end or pass through) the same point then they are co-linear (are a straight line). E.g. if you can show vector AC is a scalar multiple of vector AB then as they start at the same point they are on a straight line.
0
#10
0
#11
you people are going to be the people responsible for me passing Maths! Thanks.
1
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### How did your AQA A-level Psychology Paper 1 go?

Loved the paper - Feeling positive (273)
42.19%
The paper was reasonable (267)
41.27%
Not feeling great about that exam... (60)
9.27%
It was TERRIBLE (47)
7.26%