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I have two integrals from my calculus homework that I can't figure out how to do and I don't have any software that does symbolic calculus. If anyone could try these on Mathematica or Maple, that would be awesome. Here they are

(1-y^2)sin(y^3)

and

(1-x^2)sqrt(x^3+1)

2006-10-12 11:31:28 · 3 answers · asked by jjjones42003 5 in Science & Mathematics Mathematics

3 answers

No wonder you had troubles with these! Both are non-
elementary. Let's do each by splitting it in two.
The first one gives
int[sin(y^3) dy] - int[y^2 sin(y^3) dy]
The second integral is easy to do by substitution.
The first one, however is non-elementary.
integrals.wolfram.com evaluates it in terms of
the incomplete gamma function.
Do the second one the same way.
You get
int[ sqrt(x^3+1) dx] - int[x^2 sqrt(x^3+1) dx].
Again the second integral is easy to do by
substitution.
But the first one is the integral of the
square root of a cubic polynomial, which
makes it an elliptic integral and nonelementary.

2006-10-13 05:57:00 · answer #1 · answered by steiner1745 7 · 0 0

These are tough, even for Maple.

Send me a message and I'll send you the results in a text file. It won't format properly in here.

I should point out, Maple used special functions to describe both integrals.

2006-10-12 18:38:49 · answer #2 · answered by James L 5 · 0 0

How about solving a simpler problem first?
Try

y^2sin(y^3)

Doesn't this look more palatable? The idea is to solve a
simpler related problem, as described by Polya in the
reference.

2006-10-13 00:43:22 · answer #3 · answered by avocaronico 3 · 0 0

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