Advertisements
Advertisements
Question
if `A = [(1,2,-3),(5,0,2),(1,-1,1)], B = [(3,-1,2),(4,2,5),(2,0,3)] and C = [(4,1,2),(0,3,2),(1,-2,3)]` then compute (A + B) and (B - C). Also verify that A + (B -C) = (A + B) - C.
Solution
`A + B = [(1,2,-3),(5,0,2),(1,-1,1)] + [(3,-1,2),(4,2,5),(2,0,3)]`
`= [(1+3, 2-1, -3+2),(5+4,0+2, 2+5),(1+2,-1+0, 1+3)]`
` = [(4,1,-1),(9,2,7),(3,-1,4)]`
B- C = `[(3,-1,2),(4,2,5),(2,0,3)]-[(4,1,2),(0,3,2),(1,-2,3)]`
`= [(3-4,-1-1, 2-2), (4-0,2-3, 5-2),(2-1,0-(-2), 3-3)]`
`= [(-1,-2,0),(4,-1,3), (1,2,0)]`
`A+(B - C) = [(1,2,-3),(5,0,2),(1,-1,1)]+[(-1,-2,0),(4,-1,3),(1,2,0)]`
`= [(1+(-1), 2+(-2), -3+0),(5+4, 0+(-1), 2+3), (1+1, -1+2, 1+0)] `
`= [(0,0,-3),(9,-1,5),(2,1,1)]`
`(A + B) -C = [(4,1,-1),(9,2,7),(3,-1,4)] - [(4,1,2),(0,3,2),(1,-2,3)]`
`= [(4-4, 1-1, -1-2),(9-0, 2-3, 7-2),(3-1,-1-(-2), 4-3)] `
`= [(0,0,-3),(9,-1, 5),(2,1,1)]`
Hence, we verified that A+(B-C) = (A + B) - C .
APPEARS IN
RELATED QUESTIONS
If ` A = [(2/3, 1, 5/3), (1/3, 2/3, 4/3),(7/3, 2, 2/3)]` and `B = [(2/5, 3/5,1),(1/5, 2/5, 4/5), (7/5,6/5, 2/5)]` then compute 3A - 5B.
Simplify, `cos theta[(cos theta, sintheta),(-sin theta, cos theta)] + sin theta [(sin theta, -cos theta), (cos theta, sin theta)]`
Show that `[(5, -1),(6,7)][(2,1),(3,4)] != [(2,1),(3,4)][(5,-1),(6,7)]`
Show that `[(1,2,3),(0,1,0),(1,1,0)][(-1,1,0),(0,-1,1),(2,3,4)]!=[(-1,1,0),(0,-1,1),(2,3,4)][(1,2,3),(0,1,0),(1,1,0)]`
Find `A^2 - 5A + 6I if A = [(2,0,1),(2,1,3),(1,-1,0)]`
The product of any matrix by the scalar ______ is the null matrix.
If A `= [(1,2),(2,1)]` and f(x) = (1 + x) (1 - x), then f(a) is ____________.
If A `= [(2"x", 0),("x","x")] "and A"^-1 = [(1,0),(-1,2)],` then x equals ____________.
If | A | = | kA |, where A is a square matrix of order 2, then sum of all possible values of k is ______.