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Strange bug in int

vv 13305
November 18 2016
2


 

I found a strange bug in int.
For some functions f(x), Maple is able to compute the antiderivative (correctly) but refuses to compute the definite integral.
Or, computes the integral over 0..1  and  0..2  but refuses to compute over 1..2.

> 

int(exp(x^3), x);  #ok

-(1/3)*(-1)^(2/3)*((2/3)*x*(-1)^(1/3)*Pi*3^(1/2)/(GAMMA(2/3)*(-x^3)^(1/3))-x*(-1)^(1/3)*GAMMA(1/3, -x^3)/(-x^3)^(1/3))

 (1)
> 

int(exp(x^3), x=1..2); #?

int(exp(x^3), x = 1 .. 2)

 (2)
> 

int(exp(x^3), x=1..2, method=FTOC); #??

int(exp(x^3), x = 1 .. 2, method = FTOC)

 (3)
> 

int(exp(x^3), x=0..2); #?

int(exp(x^3), x = 0 .. 2)

 (4)
> 

int(exp(-x^3), x);  #ok

(3/4)*x*exp(-(1/2)*x^3)*WhittakerM(1/6, 2/3, x^3)/(x^3)^(1/6)+exp(-(1/2)*x^3)*WhittakerM(7/6, 2/3, x^3)/(x^2*(x^3)^(1/6))

 (5)
> 

int(exp(-x^3), x=0..2);  #ok

(3/4)*2^(1/2)*exp(-4)*WhittakerM(1/6, 2/3, 8)+(1/8)*2^(1/2)*exp(-4)*WhittakerM(7/6, 2/3, 8)

 (6)
> 

int(exp(-x^3), x=0..1);  #ok

(3/4)*exp(-1/2)*WhittakerM(1/6, 2/3, 1)+exp(-1/2)*WhittakerM(7/6, 2/3, 1)

 (7)
> 

int(exp(-x^3), x=1 .. 2);  #???

int(exp(-x^3), x = 1 .. 2)

 (8)


 

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