Hello I was looking to see if someone could look at the link

Hello. I was looking to see if someone could look at the link and answer question 29 and 31.

http://imgur.com/MB8KiLU

29) y = f(x) = x+x^2

x = 3 , delta x = .04

dy / dx = 2x + 1

or dy = (2x+1) dx

plugging the values of x and dx we get

dy = (2*3+1) .04

dy = .28

delta y = .28

31) y = f(x) = 1/x

x = 1 , delta x = .2

dy / dx = - 1/ x^2

dy = - ( 1/x^2) dx

plugging the values we get

dy = - ( 1/ 1) *.2

dy = - .2

delta y = -.2