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    7a was worded quiet awkwardly. I assumed that |W|=1, then as normal worked ot that y=x, i.e argument(Pi/4). How did you do the matrix question? I got k as 18, p as 3, a as 1, b as 4 and c as -1. The determinant with these values was zero though which doesn't seem right.
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    (Original post by 786)
    7a was worded quiet awkwardly. I assumed that |W|=1, then as normal worked ot that y=x, i.e argument(Pi/4). How did you do the matrix question? I got k as 18, p as 3, a as 1, b as 4 and c as -1. The determinant with these values was zero though which doesn't seem right.
    k was 18, p was 3 then simultaneous equations to get b^2 = 18, hence find a, b, c noting that a>0. The determinant clearly cantt be zero as M would be singular but M^-1 = 1/18 M^T so M is non-singular
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    (Original post by Bezza)
    Determinant is area/volume scaling factor so I don't think it should be negative as you can't have a negative area/volume
    its rite ... i got it 2 ... but they asked for the modulus of the det .... unless im forgetting sumthing important

    p=3
    k=18
    a b c ... i dont remember which one was which ... but one was 2root2 root2 and -2root2 ...

    i have a graphic calc and i chcek it useing the matrice funsction ...the answers work like a charm ...
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    (Original post by Bezza)
    Determinant is area/volume scaling factor so I don't think it should be negative as you can't have a negative area/volume
    how about the determinant of -1I where I is the identity matrix?
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    What answers you got for the first question?
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    (Original post by A2 student)
    What answers you got for the first question?
    remind me wat it was ?
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    (Original post by Bezza)
    Determinant is area/volume scaling factor so I don't think it should be negative as you can't have a negative area/volume
    Is it like Integration where you have a given area that is under the x-axis, hence when you calculate this you need to ignore the -ve sign and take the number value as the actual area?
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    (Original post by infekt)
    its rite ... i got it 2 ... but they asked for the modulus of the det .... unless im forgetting sumthing important

    p=3
    k=18
    a b c ... i dont remember which one was which ... but one was 2root2 root2 and -2root2 ...

    i have a graphic calc and i chcek it useing the matrice funsction ...the answers work like a charm ...
    2root2, -root2 and -2root2
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    (Original post by Checkey)
    Is it like Integration where you have a given area that is under the x-axis, hence when you calculate this you need to ignore the -ve sign and take the number value as the actual area?
    it was given in the paper " | det M | "
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    (Original post by keisiuho)
    2root2, -root2 and -2root2
    possbly ...
    wait ... i think i still have the matric saved in my calc ... lemme take a look at it
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    (Original post by A2 student)
    What answers you got for the first question?
    26660?
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    (Original post by keisiuho)
    26660?
    tht was p4 mate
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    (Original post by keisiuho)
    how about the determinant of -1I where I is the identity matrix?
    Determinant is just 1 because it doesn't change the area/volume. I just got 54sqrt2 straight out anyway so it didn't affect me!!
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    man the matrice is saved but its all in decimals in the calc ... im too lazy to do it again .. im jus happy skools over
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    (Original post by infekt)
    tht was p4 mate
    oh sorry

    2.06 and 2.13
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    (Original post by keisiuho)
    oh sorry

    2.06 and 2.13
    yup .. .hehe .. keep making me happy keisiuho
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    (Original post by Bezza)
    Determinant is just 1 because it doesn't change the area/volume. I just got 54sqrt2 straight out anyway so it didn't affect me!!
    isnt it (-1)x(-1)x(-1)=-1?
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    I got something like that too
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    (Original post by infekt)
    yup .. .hehe .. keep making me happy keisiuho
    P4 again?
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    no ... ur answers match mine ... i thought i did badly .. well i did .. but ill manage a 50 / 75
 
 
 
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