If a2 - 4a - 1 = 0 then value of a^2 + 1a^2 + 3a - 3/a is?

Answer: Option B

$$\begin{array}{rl}& a^2-4a-1=0\\ & a^2-1=4a\\ & a-\frac{1}{a}=4\\ & \text{Squring both sides}\\ & a^2+\frac{1}{a^2}-2=16\\ & \Rightarrow a^2+\frac{1}{a^2}=18\\ & \therefore a^2+\frac{1}{a^2}+3a-\frac{3}{a}\\ & =a^2+\frac{1}{a^2}+3\left(a-\frac{1}{a}\right)\\ & =18+3\times 4\\ & =18+12\\ & =30\end{array}$$