common.or
auth.dont_have_account auth.register
উৎপাদকে বিশ্লেষণ করুন: 2a2-6a-20
2a2-6a-20
= 2a2-3a-10
= 2a2-5a+2a-10
= 2{ a a-5)+2(a-5}
= 2 a-5) (a+5
.