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# C4 aqa vectors watch

1. Given that p=(3, -4) (as a vector but can’t write it on here) & q= (1, 2), find
a)...
b)|2q|
c) |p+2q|

would you do (1*2) then (2*2) & then find the magnitude or after ?
thankyou & also how bout for questions like c
2. (Original post by navpahal)
Given that p=(3, -4) (as a vector but can’t write it on here) & q= (1, 2), find
a)...
b)|2q|
c) |p+2q|

would you do (1*2) then (2*2) & then find the magnitude or after ?
thankyou & also how bout for questions like c
Bad structure on asking the question... might be why people not responding.

a) ... what?
b) 2q where q = (1,2)
c) p + 2q, where p = (3,-4) and 2q = (b)
3. would you do (1*2) then (2*2) & then find the magnitude or after ?

If this refers to part (b), it doesn't matter, you can do either. Find the magnitude of the 1,2 vector (Pythagoras) then double it OR double it first and find the magnitude of the resulting 2,4 vector.

For c, don't use your magnitude from (b), that won't help
Find the full vector
ie (3,-4) + 2(1,2) then once you've got that, find its magnitude.

|p+2q| is NOT the same as |p| + |2q|

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