A) X6 – X4 + 2X3 + 2X2= X2(X4 – X2 + 2X + 2)= X2[X2(X2 – 1) + 2(X...
Bài 1a) x
6
– x4
+ 2x3
+ 2x2
= x2
(x4
– x2
+ 2x + 2)= x2
[x2
(x2
– 1) + 2(x + 1)]= x2
. [x2
.(x -1).(x + 1) + 2(x+ 1)]= x2
(x+ 1).[x2
(x- 1)+ 2]= x2
(x + 1)(x3
– x2
+ 2)= x2
(x + 1)[(x3
+ 1) – (x2
– 1)]= x2
(x + 1).[(x + 1).(x2
– x + 1) - (x - 1).(x + 1)]= x2
(x + 1)(x + 1)( x2
– x + 1 – x + 1)= x2
(x + 1)2
(x2
– 2x + 2).b) 4x4
+ y4
= 4x4
+ 4x2
y2
+ y4
- 4x2
y2
= (2x2
+ y2
)2
- (2xy)2
= (2x2
+ y2
+ 2xy)(2x2
+ y2
- 2xy)