If x^8 + 1x^4 = 14, then the value of x^12 + 1x^6 is:

Answer: Option C

$$\begin{array}{rl}& \frac{x^8+1}{x^4}=14\\ & x^4+\frac{1}{x^4}=14\\ & x^2+\frac{1}{x^2}=4\\ & x^6+\frac{1}{x^6}=4^3-3\times 4\\ & x^6+\frac{1}{x^6}=64-12\\ & \frac{x^{12}+1}{x^6}=52\end{array}$$