2 The table shows the length, L, of the spiral from (0,0) to Corner, where k is an even number.
Term number
Length
k
1
2
2
2
4
6
3
6
12
4
8
20
n
k
n(n+1)
(a) Find a formula for n in terms of k.
(b) Use part (a) to show that the formula for the length, I., of the spiral from (0,0) to Corner is
1. = $(x+2)
(e) Show that the formula gives the correct length of the spiral from (0,0) to Comer (4)