matrices

[marsh shoal]

I need help in part b i and ii

[fathom path]

,rotate

[fathom path]

for i

i try work these out using unit vectors

unit i vector is 1 0
unit j vector is 0 1

so this is our original matrix of points

you wanna plot those two points

then reflect in the line y = -2x

T will be wherever the new positions are

is this aqa gcse fm

[marsh shoal]

y = x

0 1
1 0

[marsh shoal]

no, As Level FM

[fathom path]

calm

[marsh shoal]

mhm

would that mean then tantheta (-2)

then theta = inverse tan (-2)?

[fathom path]

sorry had to do smth

[fathom path]

2 would be positive

cos sohcahtoa is to do with lengths

and lengths cant be -ve

[fathom path]

wth is this question

@marsh shoal managed to do part i

theres probs a shorter way but i could only figure out how to do it algebraically

[marsh shoal]

I didn't yet, I'm still trying to find a way to get the matrix

[fathom path]

it involves perpendicular bisectors

its some long method i did

[marsh shoal]

ahh, I see. What answer did you get?

[fathom path]

-3/5 -4/5
-4/5 3/5

[marsh shoal]

ahhh okay ty

so I have to do the perpendicular bisector

[fathom path]

so u got ur unit vectors

which are (0,1) and (1,0) right

[marsh shoal]

yes

[fathom path]

for (0,1)

find the normal to the line y = -2x

what do u get

[marsh shoal]

this is how I did it

[fathom path]

,rotate

[marsh shoal]

I found a formula online somewhere

the the next part we use the T Matrix X by the C and D co-ordinates?

[fathom path]

yh