## Differential Equations and Linear Algebra (4th Edition)

a) $b_{12}=-1$ $b_{33}=4$ $b_{41}=0$ $b_{43}=8$ $b_{51}=-1$ $b_{52}=9$ b) $(1,3); (1,2);(2,1); (3,2)$ and $(5,1)$
a) $b_{12}$ is the element lying in the 1st row and 2nd column and it is equal to $-1$ Similarly we can find the values of all the other elements. b) Entry lying in the $1^{st}$ row and $3^{rd}$ column = Entry lying in the $1^{st}$ row and $2^{nd}$ column = Entry lying in the $2^{nd}$ row and $1^{st}$ column = Entry lying in the $3^{rd}$ row and $2^{nd}$ column = Entry lying in the $5^{th}$ row and $1^{st}$ column = -1. So, the pairs are $(1,3); (1,2);(2,1); (3,2)$ and $(5,1)$.