Viết khai triển Laurent của e^-1/z tại z = 0

Whats are the trickiest steps to do when adding or subtracting rational expressions? how does knowledge of rational numbers u in adding and subtracting rational expressions?

50 points and will mark brainlest if you were constructing a triangular frame, and you had wood in the length of 4inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood? yes or no? = explain your mathematical thinking:

Which point does not lie on the graph k(x) = 8 -3 √x a. (-64, 12) b. (125, 3) c. (343, 1) d. (8, 5)