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May 20, 2008 at 12:46 am #1671
i dont understand honours maths linear transformations at all….. nobody can explain them. if any1 knws a simple method or even another website dat cn help. my teacher cnt explain dem or my grinds teacher
thanx 
May 21, 2008 at 6:53 am #17315
are you referring to the line transformation of points or the triangle which contains of lines right. and each of there points contain coordinates..??/ if so message me and i got pretty idea how to do it….

May 21, 2008 at 4:19 pm #17316
its the line transformations of points….. if u cud help i wud b sooooooooooo happy. thanx!!!!

May 21, 2008 at 10:08 pm #17317
Hang in there. I had a full suggestion for approaching linear transfns typed in when the page expired. You will have an explanation by about 10am, Thurday morning

May 22, 2008 at 5:06 am #17318
The secret of linear tranfns. is not revealed in textbooks nor usually, alas, in class. It is this:
There are two planes, one is the ordinary xy plane (that’s a dash between x and y, not a minus sign), the other plane is an exact copy but is called the x’y’ plane. To understand linear transfns you MUST do this: draw two perp. axes on the left side of your page. Label them x and y. This is the usual xy plane
To the right of this write the letter f and underneath it an arrow –> pointing right. To the right of the arrow draw two perp. axes. Label them x’ and y’. This will be the x’y’ plane. You’re ready.
f is a magic wand that changes pretty shapes (like circles) in the xy plane into ugly shapes in the x’y’ plane. The arrow shows you in which direction this ‘magic’ flows. However because f is a LINEar transfn. it has mercy on lines (they’re kin after all) and only kicks them around a bit but doesn’t change their shape.
For example, a certain f that will be revealed later takes the line 4x – y + 5 =0 which slopes upwards in the xy plane and changes it to a line 2x’ + y’ + 6 = 0 that slopes downwards in the x’y’ plane!
To check this claim, draw the line 4x – y + 5= 0 in the xy plane. It slopes upwards, right? Now draw 2x’ + y’ + 6=0 in the x’y’ plane. It slopes downwards, right? (If you don’t know how to draw a line from its equation, ask, but the easiest way is to let x =0 first and find y, then let y = 0 and find x).
I know which f works this wicked wonder because I made up the question. Here it is : x’ = 2x and y’ = y – 1. There’s a reason why f is written this way but that’s for another time.
The Leaving Cert concentrates on getting you to find the equation of the x’y’ line in the x’y’ plane, given the xy line and the magic f. The method is in all the books but if I can help with it I will
Meanwhile, if you don’t do as I advise and draw those two planes with f and the –> between them you’re just not going to get this stuff.If you want more, ask a specific question if possible. Otherwise, beir bua.

September 6, 2008 at 9:03 pm #17319
sorry… i knw its been 15 weeks but i havent been on this in a while. it wudnt let me go onto it on my computer! thanx sooooooooooooooooooooooo much. it was really helpful!


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