3x |
x-4y |
x+y |
4y-x |
7y |
x-4y |
A.
| B.
| C.
| D.
|
3x |
x-4y |
x+y |
4y-x |
7y |
x-4y |
3x-x-y+7y |
x-4y |
2x+6y |
x-4y |
1 |
1×2 |
1 |
2×3 |
1 |
n(n+1) |
m2 |
m-n |
n2 |
n-m |
A.m+n | B.m-n | C.-m+n | D.-m-n |
a2-1 |
a2-2a+1 |
2a-a2 |
a2-a-2 |
A.-
| B.-
| C.1 | D.-
|
x |
x2-x+1 |
1 |
x |
A.
| B.
| C.6 | D.8 |
-2ac2 |
14a2bc |
1 |
x-2 |
1 |
x+2 |
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