I am not sure how to set these problems up in Excel. I need guidance as to which equations to use to find the solution.

Use Central Difference; use 4 segments (3 internal nodes); compare to exact solution. For problem 1 and 2, you may solve either using excel or matlab- but make sure what you submit has the steps and the matrix setup providing final solution on its own will not receive credit. 1. -u" = 2sin (m) in the interval 0