Question
Approximate the change in the lateral surface area(excluding the area of the base) of a right circular cone fixed height of h = 6m when its radius decreases from r=9m to r=8.9m (S=(pi)r sqrt(r^2+h^2)).
Answers
bobpursley
surface area= PI*r (sqrt(h^2+r^2)
A=PI (sqrt(r^4+(rh)^2)
dA=PI (1/2)(4r^3+2rh^2)/sqrt(r^4+(rh)^2)* dr
dr=-.1
r=9
h=6
A=PI (sqrt(r^4+(rh)^2)
dA=PI (1/2)(4r^3+2rh^2)/sqrt(r^4+(rh)^2)* dr
dr=-.1
r=9
h=6