Feb 25, 2007 #1 pmonon Full Member level 3 Joined Jan 28, 2006 Messages 152 Helped 7 Reputation 14 Reaction score 1 Trophy points 1,298 Activity points 2,232 I am in trouble with this definite integral: ∫ x * exp(-((2*x)^-2)) dx from -≈ to ≈ Anyone, please?
Feb 25, 2007 #2 J joyu Newbie level 5 Joined Feb 11, 2007 Messages 10 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 1,365 u sub u=x^2 remember you can write it as x*exp[1/(4x^2)] Edit: Umm, nevermind you cant integrate e^(1/u) Added after 18 minutes: my calculator says its impossible
u sub u=x^2 remember you can write it as x*exp[1/(4x^2)] Edit: Umm, nevermind you cant integrate e^(1/u) Added after 18 minutes: my calculator says its impossible
Feb 25, 2007 #3 pmonon Full Member level 3 Joined Jan 28, 2006 Messages 152 Helped 7 Reputation 14 Reaction score 1 Trophy points 1,298 Activity points 2,232 It is a problem here to type in the expressions, let me try again: I need to calculate this definite integral ∫ x*exp{-1/(2*x2)} dx from -infinity to infinity...
It is a problem here to type in the expressions, let me try again: I need to calculate this definite integral ∫ x*exp{-1/(2*x2)} dx from -infinity to infinity...
Feb 25, 2007 #4 J joyu Newbie level 5 Joined Feb 11, 2007 Messages 10 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 1,365 x2?
Feb 25, 2007 #5 P pixel Advanced Member level 2 Joined Sep 16, 2004 Messages 508 Helped 69 Reputation 138 Reaction score 16 Trophy points 1,298 Activity points 3,993 Result= 0 (odd function and symetrical integration range from -a to +a)
Feb 25, 2007 #6 pmonon Full Member level 3 Joined Jan 28, 2006 Messages 152 Helped 7 Reputation 14 Reaction score 1 Trophy points 1,298 Activity points 2,232 joyu said: x2? Click to expand... I mean x squared