The correct options are
A If k∈(−1,1), then α+β=2
D If k∈(1,3), then α+β=6
f:R−{−1,k}→R−{α,β}
f(x)=(2x−1)(2x2−4px+p3)(x+1)(x2−p2x+p2)
For the domain to be R−{−1,k},k must be a repeated root of x2−p2x+p2=0
∴p4−4p2=0⇒p2(p2−4)=0
∴p=0,±2, but p≥0
⇒p=0,2
For p=0,k=0
f(x)=(2x−1)(2x2)(x+1)(x2)
⇒Df=R−{−1,0}, Rf=R−{4,−2}
∴α+β=2
For p=2,k=2
f(x)=(2x−1)2(x−2)2(x+1)(x−2)2
⇒Df=R−{−1,2}, Rf=R−{4,2}
∴α+β=6