my guide for matrices of transformation!! :)

[igcse student 5558]

how to find the coordinates of the point of intersection of y=4-x and the parabola y=x^2+1

 

[Mariam Ash]

so some people have asked me for how i do matrices of transformation...and i will post it here so everyone can see!!!

alright so the way i memorise this is by using mnemonics( like making each number stand for something, u will see). memorise in this order!
For THESE matrices i make the whole matrix stand for the word ollo ( its kinda like an insult ) so 0110 is ollo get it?

reflection y=x
(0 1
1 0)
i call this ollo
reflection y=-x
( 0 -1
-1 0)
i call this ollo with all minus
rotation 90 anticlockwise
( 0 -1
1 0)
i call this ollo with top minus
rotation 90 clockwise
( 0 1
-1 0)
i call this ollo with bottom minus
For THESE matrices i make the whole matrix stand for the word lool ( kinda like lol) so 1001 is lool
rotation 180
( -1 0
0 -1)
i call this lool with all minus
reflection y axis
( -1 0
0 1)
i call this lool with top minus
reflection x axis
( 1 0
0 -1)
i call this lool with bottom minus
For THESE matrices i made up a STORY so look!
shear x axis
( 1 k
0 1)
i made these numbers stand for IS KHALED ON LINE?
so 1= is k= khaled 0= on 1= line
shear y axis
(l 0
k 1)
i made this one a word: local = lokl = 10k1
stretch y axis
( k 0
0 l)
this is also a word: cool = kool = k001
stretch x axis
( 1 0
0 k)
this is also a word: look = 100k
FINALLY
enlargement ( only one thank god )
(k 0
0 k)
i made it stand for cook = k00k
HOPE I HELPED AND INSHALLAH U WILL UNDERSTAND AND DO GOOD

file is attached below( some minor changes to the mnemonics too ), kindly made by wooowooowoo ( long name i know )

In this attached file.....ther r many things wich r opposite of wat u wrote...check stretch...wich one shud we learn ???

 

[wooowooowoo]

In this attached file.....ther r many things wich r opposite of wat u wrote...check stretch...wich one shud we learn ???

Learn from the one specified in thread. I might have done some copy - paste error while rendering. Can you please private message me about what all things are wrong?

 

[cardude456]

Thanks bro

 

[shesmycocaine]

how to find the coordinates of the point of intersection of y=4-x and the parabola y=x^2+1

you sketch the parabola and then you sketch y=4-x . Where they intersect (a point or two), draw a perpendicular to the x-axis and that will be you (x). Next draw the perpendicular to the y-axis and that will be your . The coordinates are (x,y)

 

[beewhiz997]

Thanks bro

dude...im a girl

 

[Mariam Ash]

Learn from the one specified in thread. I might have done some copy - paste error while rendering. Can you please private message me about what all things are wrong?

ohh okay thanks !

 

[beewhiz997]

Learn from the one specified in thread. I might have done some copy - paste error while rendering. Can you please private message me about what all things are wrong?

the lokl one is different, as is the ikol one. double check

 

[wooowooowoo]

Sorry about the previous post - Messed up the stretching part. I request everyone to delete the old file and download the updated version.

 

[cardude456]

dude...im a girl

opps......sorry

 

[Lostsoul]

and how do you get the invariant line of shear and stretchh, its kinda confusingg.. Helpp

 

[beewhiz997]

and how do you get the invariant line of shear and stretchh, its kinda confusingg.. Helpp

for invariant line:

STRETCH- if the point moved is parallel to the Y AXIS it is X AXIS invariant and same for opposite
SHEAR- if the point moved is parallel to the Y AXIS it is Y AXIS invariant and same for opposite

get it ? shear and stretch are different hope i helped!

 

[cyanide360]

Thanks alot.

 

[Fadel.Gaber]

I don't get it. I already know these matrices from the making scheme. BUT how do you find them? I don't want to just memorize these without knowing the theory and just write them in the exam.