Question

please do it fast
and good night.​

Answer 1

Step-by-step explanation:

identity used : x² - y² = (x+y)(x-y)

here x = a²+b²-c² and y = 2ab

=> [a²+b²-c²+2ab][a²+b²-c²-2ab]

=> [ (a+b)² - c²][(a-b)² - c²]

=> (a+b+c)(a+b-c)(a-b+c)(a-b-c)