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Therefore, from the uniqueness of the additive inverse proved in the above Problem addinvrstunique,
it follows that .
Consider the matrices .
Find the following if possible. If it is not possible explain why.
(a)
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(b)
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(c)
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Not possible
(d)
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(e)
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Not possible
(f)
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Not possible
Let . Find all matrices, such that
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Solution is: so the matrices are of the form
Let Is it possible to choose such that If so, what should equal?
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Thus you must have . Therefore .
Find matrices and such that and but .
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Let
Suppose and is an invertible matrix. Does it follow that Explain why or why
not.
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Yes . Multiply on the left by .
Let
Find if possible. If does not exist, explain why.
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Let
Find if possible. If does not exist, explain why.
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The reduced row echelon form is . There is no inverse.
Show that if exists for an matrix, then it is unique. That is, if and then
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Show that if is an invertible matrix, then so is and
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You need to show that acts like the inverse of because from uniqueness in
the above problem, this will imply it is the inverse. From properties of the
transpose,
Hence and this last matrix exists.
Show by verifying that
and
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Find an factorization of the coefficient matrix and use it to solve the system of
equations.
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An factorization of the coefficient matrix is First solve which gives Then solve
which says that and
Find an factorization of the coefficient matrix and use it to solve the system of
equations.
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An factorization of the coefficient matrix is First solve which yields . Next solve
This yields