Question

A skier has decided that on each trip down a slope, she will do 2 more jumps than before. On her first trip she did 6 jumps. Derive the sigma notation that shows how many total jumps she attempts from her fourth trip down the hill through her twelfth trip. Then solve for the number of total jumps from her second to tenth trips.

Answer 1

∑i=2i=10(4+2n)= You can do it by hand, w/o much work . plug in n=2 into (4+2n) then plug in n=3 into (4+2n) then plug in n=4 into (4+2n) etc until you get to n=10. Add them all up.
add 8 + 10 + 12 + 14 + 16 + 18 + 20 + 22 + 24
144 jumps!