What is the arclength of f(x)=e^(1/x)/x-e^(1/x^2)/x^2+e^(1/x^3)/x^3 on x in [1,2]?

1 Answer
Oct 23, 2016

Computed by WolframAlpha
The arclength is 7.01539

Explanation:

Arclength along a curve

s = int_a^b sqrt(1 + (f'(x))^2)dx

The derivative as computed by WolframAlpha

f'(x) = -e^(1/x)/x^3-e^(1/x)/x^2-(3 e^(1/x^3))/x^7-(2 e^(1/x^2))/x^5-(3 e^(1/x^3))/x^4-(2 e^(1/x^2))/x^3

This is the definite integral:

s = int_1^2 sqrt(1 + (-e^(1/x)/x^3-e^(1/x)/x^2-(3 e^(1/x^3))/x^7-(2 e^(1/x^2))/x^5-(3 e^(1/x^3))/x^4-(2 e^(1/x^2))/x^3)^2)dx

Arclength as computed by WolframAlpha

s = 7.01539