x2-1-y(y-2) এর উৎপাদক কত ?
A
(x-y-1) (x-y+1
B
(x-y+1) (x+y-1)
C
(x+y+1) (x-y-1)
D
(x-y) (x+y+1)
Correct Answer: (x-y+1) (x+y-1)
x² - 1 - y(y - 2) = x² - 1 - y² + 2y = x² - (y2 - 2y + 1) = x² - (y - 1)² = (x - y + 1) (x + y - 1)