Vectors C4

For Part c, I had to look at the Mark scheme as I didn't get the answer, and whilst I understand what it's done, I would like to know more tips to get to the answer, as I think if you gave me another similar problem, I wouldn't have the 'inspiration' to get to the answer? (If u get what I mean)

Screen Shot 2016-09-01 at 19.20.35.png51.7KB

Reply 1

B_9710

18

To show that VTA is a straight line you will need to show that

\vec{VA} = k(\vec{VT})

where

k

is a scalar constant.
Maybe let

\vec{VF}= 3\mathbf{a}

and

\vec{MF} = 4\mathbf{b}

.
To show that VTA is a straight line, you are showing that the points V, T and A are collinear.

(edited 7 years ago)

Reply 2

Xphoenix

OP

18

Original post by B_9710

To show that VTA is a straight line you will need to show that

\vec{VA} = k(\vec{VT})

where

k

is a scalar constant.
Maybe let

\vec{VF}= 3\mathbf{a}

and

\vec{MF} = 4\mathbf{b}

.
To show that VTA is a straight line, you are showing that the points V, T and A are collinear.

Didn't realise how simple this actually is... So if we think away from this problem but more into exam questions, for this type of problem to show certain points are a straight line, would you always try and show they are colinear and multiplied by a constant?

Original post by Xphoenix

Didn't realise how simple this actually is... So if we think away from this problem but more into exam questions, for this type of problem to show certain points are a straight line, would you always try and show they are colinear and multiplied by a constant?