The Total solution for NCERT class 6-12
a2 – b2 + 2bc – c2= a2 – (b2 – 2bc + c2) {∵ a2 + b2 –2abc = (a – b)2}= a2 – (b – c)2= (a)2 – (b – c)2 {∵ a2 – b2 =(a + b) (a – b)}= (a + b – c) (a – b + c)