How do you integrate #\int \frac { t ^ { 2} } { \sqrt { 1- t ^ { 6} } } d t#?
1 Answer
Sep 5, 2017
# int \ t^2/(sqrt(1-t^6)) \ dt = 1/3 \ arcsin(t^3) + C #
Explanation:
We seek:
# I = int \ t^2/(sqrt(1-t^6)) \ dt #
Let us perform a substitution;
put
#u=t^3 => (du)/dt = 3t^2 #
Substituting into the integral we get:
# I = 1/3 \ int \ (3t^2)/(sqrt(1-t^6)) \ dt #
# \ \ = 1/3 \ int \ (1)/(sqrt(1-u^2)) \ du #
Which is a standard integral, and so:
# I = 1/3 \ arcsin(u) + C #
And, restoring the substitution, we get:
# I = 1/3 \ arcsin(t^3) + C #