What is the antiderivative of #xsqrtx#?

2 Answers
Jul 27, 2015

You can simply multiply them together (more explicitly).

#xsqrtx = x^("3/2")#

And then just use the reverse Power Rule.

#d/(dx)[x^("3/2")] = 2/5x^("5/2")#

Then, since an antiderivative is a generalization of what an integral does, they are almost the same thing. Therefore, we add a constant to imply that you get every single function that is within the antiderivative's slope field.

http://www.mathscoop.com/

(notice the various vertical-shift variations of a single function forms the slope field)

#-> color(blue)(2/5x^("5/2") + C)#

Jul 27, 2015

# 2/5 x^(5/2) #

Explanation:

Note : # x sqrt(x) = x x^(1/2) = x^(1 + 1/2) = x^(3/2) #
Therefore, # int x sqrt(x) dx = int x^(3/2) dx = (x^(3/2 + 1)) / (3/2 + 1) = 2/5 x^(5/2) #