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    Name:  photo (3).jpg
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Size:  493.6 KBThat is the question --->https://gyazo.com/1b63be4386c27e06262b5f45656ab95e

    Where have I gone wrong?
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    Well you've "pre-multiplied" on the the LHS and "post-multiplied" on the RHS.

    AB = C \Rightarrow A^{-1} AB = A^{-1}C

    Recall that matrix multiplication is (in general) not commutative!
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    (Original post by Indeterminate)
    Well you've "pre-multiplied" on the the LHS and "post-multiplied" on the RHS.

    AB = C \Rightarrow A^{-1} AB = A^{-1}C

    Recall that matrix multiplication is (in general) not commutative!
    Please define commutative for me
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    (Original post by Psst.)
    Please define commutative for me
    Oops, sorry

    Addition is commutative because, eg, 3+4 = 4+3.
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    (Original post by Indeterminate)
    Oops, sorry

    Addition is commutative because, eg, 3+4 = 4+3.
    No need to apologise for my retardiness

    Thanks again!
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    (Original post by Psst.)
    Please define commutative for me
    \cdot is commutative on X iff a\cdot b = b\cdot a \forall a, b \in X
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    (Original post by Psst.)
    No need to apologise for my retardiness

    Thanks again!
    :hat2:

    Tbf you're unlikely to get any exposure to this kind of terminology at A-level, so you're ok!
 
 
 
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