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

Watch
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 4 years ago
#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
reply
gdunne42
Badges: 21
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 4 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
reply
the bear
Badges: 20
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report 4 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
reply
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#4
Report Thread starter 4 years ago
#4
ah, thanks. that's really helpful. but does the multiply have to be a whole number?
0
reply
RDKGames
Badges: 20
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#5
Report 4 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
reply
gdunne42
Badges: 21
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#6
Report 4 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
reply
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#7
Report Thread starter 4 years ago
#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
reply
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#8
Report Thread starter 4 years ago
#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
reply
gdunne42
Badges: 21
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#9
Report 4 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
reply
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#10
Report Thread starter 4 years ago
#10
ah... i hadn't thought about that..
0
reply
WarHammer-
Badges: 1
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#11
Report Thread starter 4 years ago
#11
you people are going to be the people responsible for me passing Maths! Thanks.
1
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

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

Personalise

What is your favourite revision method?

Taking notes manually (65)
22.65%
Note taking apps (6)
2.09%
Flashcards (55)
19.16%
Revision guides (16)
5.57%
Past papers (133)
46.34%
Something else (let us know in the thread) (12)
4.18%

Watched Threads

View All