2
展開下列各式:
(1) (a+b)(a¹-a³b+ a²b²ab³ + b^)=
a²-a7b + a²b-a7b²ab²+ ob-as tab²-a5+ +6²
= as tbs
(2) (x+y+z)² + (x + y −z)² + (x−y+z)² + (-x+y+z)² =
O
+(-x + 7 + 2)/ X+Y+Z)
7)
(3) (a² + ab + b²)(a² - ab + b²)(a − a²b² + b^)=,
- (at - abtab tabab²+ab + a²b²-ab² +b^) (a^_c²b² +6²)
= (a² + a²b²³+b^) (a²_²²b²+6²) = a² + a²b²¹ + b ²
(4) (a-2b-c)(a² +4b² +c² + 2ab-2bc + ac) =
【Ans (1) a³ + b³ (2) 4(x² + y² +2²) (3) a² + ab + b³ (4) a³-8b³-c³-6abc 】