- #1
Cmunro
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The question is as follows:
Solve for a: |(a-1) ( 1) (0) |
....|(-10) (a+1) (a^2) | =0
....|(2a) ( 2) (-1) |
(Sorry that is my attempt at the determinant of a 3x3 matrix - the brackets are there to show which bit goes with which as they seem to group together)
My calculations: a-1(-a-1-2a^2) + (2a^3 -10)
-2a^2-2a-a^2-a-a-1-2a^3-10=0
2a^3-3a^2-4a-11=0
Since we have not covered binomial expansion yet..I can only assume that I have made a mistake in the calculations here. Any suggestions?
Thank you!
Solve for a: |(a-1) ( 1) (0) |
....|(-10) (a+1) (a^2) | =0
....|(2a) ( 2) (-1) |
(Sorry that is my attempt at the determinant of a 3x3 matrix - the brackets are there to show which bit goes with which as they seem to group together)
My calculations: a-1(-a-1-2a^2) + (2a^3 -10)
-2a^2-2a-a^2-a-a-1-2a^3-10=0
2a^3-3a^2-4a-11=0
Since we have not covered binomial expansion yet..I can only assume that I have made a mistake in the calculations here. Any suggestions?
Thank you!
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