Question

plz friends answer me with solution​

Answer 1

(a-1) / p(a) = (a²+a+1)/(a³-1) and we know that

a³ - 1 = (a-1)(a²+a+1) then

(a -1)/p(a) = (a²+a+1)/(a-1)(a²+a+1)

or, (a -1) /p(a) = 1/(a - 1)

or, p(a) = (a -1 )²

Hence, the option D is correct.