Question 1
1.1 Given that u = (6 - :i:, 4 - y) and v = (x - 4, y + 2) arc vectors in JR2 , such that u = v,
solve for x and y?
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1.2 Determine a unit vector perpendicular to both of the vectors A = c + d and B = c - d,
where c = 3i + 2j + 2k and d = i + 2j - 2k.
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1.3 Consider the vectors z = (3 + 4i, 2 - i) and w = (1 + 3i, 1 - 2i) in C2 . Determine whether
z and w are orthogonal.
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1.4 Prove that if x and y are orthogonal vectors in R"', then show that
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Question 2
2.1 ·write down a 4 x 4 matrix whose i/h entry is given by a.,j = ij~-l, and comment on your
matrix.
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2.2 Let A be a square matrix. State what is meant by each of the following statements.
(a) A is symmetric
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(b) A is orthogonal
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(c) A is skew-symmetric
[l]
2.3 Conside, the matcL, A - ( ~l ; ~5 ) .
a) Use the Cofactor expansion method along the second col-u,mnto evaluate the determi-
nant of A.
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b) Is A invertible? If it is, Use the Gauss-.Jon.lan Elimination method to find A- 1. [14]
c) Find <let (3(2A)- 1).
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