Eagerissac
New member
- Joined
- Jan 9, 2020
- Messages
- 16
So I keep getting 2. ii) wrong below and I'm not sure what I'm doing incorrectly in my steps. I began by placing the values of the tuples in a 4x5 matrix consisting of:
Using RREF, I got it simplified to:
I'm getting stumped because I'm not exactly sure what I'm supposed to do with column 3 since it's a free variable. I assumed I would just ignore the 3rd column as well as the 3rd tuple given in the question. I did the following:
2(0 + 2x + 2x^2 + 1x^3) - 4(2 - x + 2x^2 + 2x^3) + 0(-1 + 0x + (-1)x^2 + 1x^3)
=0 + 4x + 4x^2 + 2x^3 - 8 + 4x - 8x^2 - 8x^3
=-8 + 8x - 4x^2 - 6x^3
but it keeps getting marked as wrong. I tried to just count the free variable/third column and tuple in anyways to see what happens but the new answer I got is also marked wrong. Are there steps that I'm missing or doing wrong completely? I would appreciate some help. I redid the RREF and substitutions multiple times but I keep getting the original answer that I got. I don't think I made a calculation error so I'm assuming there's something I'm not getting.
1 | 0 | -2 | 2 | 4 |
2 | 1 | -7 | 3 | 3 |
1 | 1 | -5 | 2 | 0 |
-3 | -2 | 12 | -5 | -3 |
Using RREF, I got it simplified to:
1 | 0 | -2 | 0 | 2 |
0 | 1 | -3 | 0 | -4 |
0 | 0 | 0 | 0 | 1 |
0 | 0 | 0 | 1 | 0 |
I'm getting stumped because I'm not exactly sure what I'm supposed to do with column 3 since it's a free variable. I assumed I would just ignore the 3rd column as well as the 3rd tuple given in the question. I did the following:
2(0 + 2x + 2x^2 + 1x^3) - 4(2 - x + 2x^2 + 2x^3) + 0(-1 + 0x + (-1)x^2 + 1x^3)
=0 + 4x + 4x^2 + 2x^3 - 8 + 4x - 8x^2 - 8x^3
=-8 + 8x - 4x^2 - 6x^3
but it keeps getting marked as wrong. I tried to just count the free variable/third column and tuple in anyways to see what happens but the new answer I got is also marked wrong. Are there steps that I'm missing or doing wrong completely? I would appreciate some help. I redid the RREF and substitutions multiple times but I keep getting the original answer that I got. I don't think I made a calculation error so I'm assuming there's something I'm not getting.