A sequence u1,u2,u3,… u_1, u_2, u_3, \dots\,u1,u2,u3,… is defined by
u1=6un+1=−12un,n≥1 \begin{aligned}u_1 &= 6 \\u_{n+1} &= -\frac{12}{u_n}, \quad n \geq 1\end{aligned} u1un+1=6=−un12,n≥1Find u2,u3 u_2, u_3\,u2,u3 and u4u_4u4.
Write down the value of u100u_{100}u100.
