Answer :
Answer:
(ab+a-b+1)(ab-a+b+1)
Step-by-step explanation:
- (1 - a²) (1 - b²) + 4ab=
- 1 -a²-b² +a²b² +4ab =
- (a²b² +2ab +1 )- (a²-2ab+b²)=
- (ab+1)² - (a-b)²=
- (ab+1 +a-b)(ab+1 -a+b)=
- (ab+a-b+1)(ab-a+b+1)
Answer:
(ab+a-b+1)(ab-a+b+1)
Step-by-step explanation: