- #1
ichivictus
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This is from Schaum's 3000 solved Physics problems (1.75). The teacher attempted to guide us to solve it but me and a few classmates are still struggling to figure this out.
Vector A = 3i + 5j - 2k
Vector B = -3j + 6k
Find a Vector C such that 2A + 7B + 4C = 0
This looks a lot like Linear Algebra, something I am not particularly skilled in, however I think I gave it a decent shot.
Ax = 3
Ay = 5
Az = -2
Bx = -3
Bz = 6
2(3) + 7(-3) + 4(Cx) = 0
Cx = 15/4 = 3.75
2(5) + 0 + 4(Cy) = 0
Cy = -10/4 = -5/2 = -2.5
2(-2) + 7(6) + 4(Cz) = 0
Cz = -38/4 = -19/2 = -9.5
So therefor Vector C = (15/4)i - (5/2)j - (19/2)k
The real solution is C = -1.5i + 2.75j - 9.5k
Looks like I got Cz correct, but I can't figure out how to get Cx and Cy.
Homework Statement
Vector A = 3i + 5j - 2k
Vector B = -3j + 6k
Find a Vector C such that 2A + 7B + 4C = 0
The Attempt at a Solution
This looks a lot like Linear Algebra, something I am not particularly skilled in, however I think I gave it a decent shot.
Ax = 3
Ay = 5
Az = -2
Bx = -3
Bz = 6
2(3) + 7(-3) + 4(Cx) = 0
Cx = 15/4 = 3.75
2(5) + 0 + 4(Cy) = 0
Cy = -10/4 = -5/2 = -2.5
2(-2) + 7(6) + 4(Cz) = 0
Cz = -38/4 = -19/2 = -9.5
So therefor Vector C = (15/4)i - (5/2)j - (19/2)k
The real solution is C = -1.5i + 2.75j - 9.5k
Looks like I got Cz correct, but I can't figure out how to get Cx and Cy.