C-03-Q108mediumsingle_mcqFactorize a2−1+2b−b2a^2 - 1 + 2b - b^2a2−1+2b−b2:a(a+b−1)(a−b+1)(a+b-1)(a-b+1)(a+b−1)(a−b+1)b(a−b−1)(a+b+1)(a-b-1)(a+b+1)(a−b−1)(a+b+1)c(a+1)(a−1)(b−1)(a+1)(a-1)(b-1)(a+1)(a−1)(b−1)d(a+b)(a−b)(a+b)(a-b)(a+b)(a−b)ব্যাখ্যাGroup as a2−(1−2b+b2)=a2−(1−b)2a^2-(1-2b+b^2)=a^2-(1-b)^2a2−(1−2b+b2)=a2−(1−b)2, a difference of squares. This gives (a+(1−b))(a−(1−b))=(a−b+1)(a+b−1)\big(a+(1-b)\big)\big(a-(1-b)\big)=(a-b+1)(a+b-1)(a+(1−b))(a−(1−b))=(a−b+1)(a+b−1), which is the same as option (a).