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    (Original post by Number Nine)
    I'm a see what unofficial says on that but think I got it

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    How did you do it?
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    (Original post by C0balt)
    How did you do it?
    Subbed in y = mx + c and showed it works for m = -1 and any value of c

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    (Original post by Number Nine)
    Subbed in y = mx + c and showed it works for m = -1 and any value of c

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    **** I thought of doing 3+2m=-2m-1 but I didn't in the end...
    I just subbed into y'=mx'+c and didn't know what to do afterwards
    But I think I had 4-4m+c=0 or something like that but the if m=-1 then c cannot be any value can it
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    (Original post by C0balt)
    **** I thought of doing 3+2m=-2m-1 but I didn't in the end...
    I just subbed into y'=mx'+c and didn't know what to do afterwards
    But I think I had 4-4m+c=0 or something like that but the if m=-1 then c cannot be any value can it
    After doing y' = mx' + c I just showed cos I factored -2(m+1)(c+2) when m = -1 c can have any value as the whole expression is 0

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    (Original post by Number Nine)
    After doing y' = mx' + c I just showed cos I factored -2(m+1)(c+2) when m = -1 c can have any value as the whole expression is 0

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    Ah that's clever
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    (Original post by C0balt)
    Ah that's clever
    Cheers fam



    Are we the only two who have sat it lol
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    What are people saying about predicted grade boundaries for that?
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    (Original post by Barbecuetime123)
    What are people saying about predicted grade boundaries for that?
    Note yet

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    (Original post by Number Nine)
    Cheers fam



    Are we the only two who have sat it lol
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    Appears that way

    Did y'=mx'+c then got (3+2m)x+(-2m-1)y+4-4m+c=0 or something which hopefully gets me a mark or two lmao

    How did you find the paper overall? I
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    (Original post by C0balt)
    Appears that way

    Did y'=mx'+c then got (3+2m)x+(-2m-1)y+4-4m+c=0 or something which hopefully gets me a mark or two lmao

    How did you find the paper overall? I
    Then you sub in y = mx + c

    Alright pretty standard think I got most **** bar like posting a comment on why pi1 and pi3 don't meet.

    You?

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    My answers. Some of these may be wrong.
    1) 3root22/2
    2)detb =-1/32 (cant remember exactly)
    3)-7(a-4)(a+1)(cant remember third factor)
    4)z= 17/4 a
    x =-11/6 a
    Y= cant remember
    5) p=-11
    Lambda =2, -2,7
    6) y=3/2 x -2
    All lines of the form y=3/2 x +k are invariant lines (edit: I believe this is wrong)
    7) k = 1/8
    T2: rotation 150° about y-axis
    8) k=+-1
    When k =1, two parallel planes, intersecting third plane
    When k=-1, planes form a triangular prism.
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    (Original post by Number Nine)
    Then you sub in y = mx + c

    Alright pretty standard think I got most **** bar like posting a comment on why pi1 and pi3 don't meet.

    You?

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    I got y=-x+c was invariant under T hence infinite invariant lines.

    Triangle was (3/2)root22 or (1/2)root22 I don't remember.

    P was -11 i think.

    I can't remember the rest, the last question with the variable planes and inconsistency, seemed a lot for 4 marks.
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    (Original post by Qcomber)
    My answers. Some of these may be wrong.
    1) 3root22/2
    2)detb =-1/32 (cant remember exactly)
    3)-7(a-4)(a+1)(cant remember third factor)
    4)z= 17/4 a
    x =-11/6 a
    Y= cant remember
    5) p=-11
    Lambda =2, -2,7
    6) y=3/2 x
    All lines of the form y=3/2 x +k are invariant lines
    7) k = 1/8
    T2: rotation 150° about y-axis
    8) k=+-1
    When k =1, two parallel planes, intersecting third plane
    When k=-1, planes form a triangular prism.
    a-1 was 3rd factor, i think

    I think you messed up something on 6.
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    (Original post by Number Nine)
    Then you sub in y = mx + c

    Alright pretty standard think I got most **** bar like posting a comment on why pi1 and pi3 don't meet.

    You?

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    Yeah it wasn't much different to past papers surprisingly
    Though I disliked how the solutions for x y z where you had to use inverse matrix were messy fractions (I belive so anyway)
    Oh yeah I hate commenting thing too, I said for k=1 pi1 and pi3 are parallel so no common line of intersection and for k=-1 I said they form a prism idk if that's right lol
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    (Original post by Qcomber)
    My answers. Some of these may be wrong.
    1) 3root22/2
    2)detb =-1/32 (cant remember exactly)
    3)-7(a-4)(a+1)(cant remember third factor)
    4)z= 17/4 a
    x =-11/6 a
    Y= cant remember
    5) p=-11
    Lambda =2, -2,7
    6) y=3/2 x -2
    All lines of the form y=3/2 x +k are invariant lines
    7) k = 1/8
    T2: rotation 150° about y-axis
    8) k=+-1
    When k =1, two parallel planes, intersecting third plane
    When k=-1, planes form a triangular prism.
    I got -32 for 2
    y=3/2x-2 for line of invariant points
    210 degrees for rotation (same thing?)
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    (Original post by Qcomber)
    My answers. Some of these may be wrong.
    1) 3root22/2
    2)detb =-1/32 (cant remember exactly)
    3)-7(a-4)(a+1)(cant remember third factor)
    4)z= 17/4 a
    x =-11/6 a
    Y= cant remember
    5) p=-11
    Lambda =2, -2,7
    6) y=3/2 x -2
    All lines of the form y=3/2 x +k are invariant lines
    7) k = 1/8
    T2: rotation 150° about y-axis
    8) k=+-1
    When k =1, two parallel planes, intersecting third plane
    When k=-1, planes form a triangular prism.
    Got pretty much the same, think Y was -41/12 a? I didn't cancel down though, so got -44/24, -82/24 and 102/24, do you think I'd lose a mark?
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    (Original post by C0balt)
    I got -32 for 2
    y=3/2x-2 for line of invariant points
    210 degrees for rotation (same thing?)
    As long as you put which sense it is. The matrices on the formula sheet are for anticlockwise rotations.
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    what did you guys put for the question (i think 6 ?) where it asked you basically for the definition of invariant lines ?

    +for question 4 i think i got integer coefficients and i can't remember any of 6 but i think the rest of mine were the same as what you're discussing ^ if i'm remembering right
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    What did everyone think of it ?
    I personally didn't like 5,6 or 7 :/
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    (Original post by Roxanne18)
    What did everyone think of it ?
    I personally didn't like 5,6 or 7 :/
    i didnt like 6 either. i thought it was a bit of a weird paper tho like the first few were nice and then the rest were kind of awful ?? like doable but not nice you know ??
 
 
 
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