While we cannot formally take the log of zero, it makes sense to define the log-likelihood of a shifted exponential to be ℓ(λ,a)=(nlnλ−λ∑i=1n(Xi−a))1mini(Xi) ≥a+(−[infinity])1mini(Xi)

Answer to your question: a. the fundamental theorem of algebra tells you that the equation will have two complex roots since the degree of the polynomial is 2. the roots are ​ x=1±i7√2 .number of roots=degree of polynomialhere, degree of polynomial is 2 so number of roots will be 2.hope it *_*