S ScarFace93 New Member Joined Apr 8, 2010 Messages 9 Gender Male HSC 2010 Apr 15, 2010 #1 how do you integrate this ? 1/(e^2x + e^x) thanks
N nikkifc Member Joined Apr 8, 2010 Messages 70 Gender Female HSC 2010 Apr 15, 2010 #2 ScarFace93 said: how do you integrate this ? 1/(e^2x + e^x) thanks Click to expand... Let u=e^x du/dx=e^x = u
ScarFace93 said: how do you integrate this ? 1/(e^2x + e^x) thanks Click to expand... Let u=e^x du/dx=e^x = u
shaon0 ... Joined Mar 26, 2008 Messages 2,029 Location Guess Gender Male HSC 2009 Apr 15, 2010 #3 nikkifc said: Let u=e^x du/dx=e^x = u Click to expand... Thats incorrect. Divide by e^2x. I=S dx/e^2x+e^x = -S e^-x.-e^-x/(1+e^-x) dx = -S u du/(1+u) = S 1/(u+1) -1 du = ln(u+1)-u +C = ln(e^-x+1)-e^-x+C Last edited: Apr 15, 2010
nikkifc said: Let u=e^x du/dx=e^x = u Click to expand... Thats incorrect. Divide by e^2x. I=S dx/e^2x+e^x = -S e^-x.-e^-x/(1+e^-x) dx = -S u du/(1+u) = S 1/(u+1) -1 du = ln(u+1)-u +C = ln(e^-x+1)-e^-x+C
N nikkifc Member Joined Apr 8, 2010 Messages 70 Gender Female HSC 2010 Apr 15, 2010 #4 shaon0 said: Thats incorrect. Divide by e^2x. Click to expand... Whoops. I shouldn't do maths after a long day. haha
shaon0 said: Thats incorrect. Divide by e^2x. Click to expand... Whoops. I shouldn't do maths after a long day. haha
shaon0 ... Joined Mar 26, 2008 Messages 2,029 Location Guess Gender Male HSC 2009 Apr 15, 2010 #5 nikkifc said: Whoops. I shouldn't do maths after a long day. haha Click to expand... Yeah, nw.
F fullonoob fail engrish? unpossible! Joined Jul 19, 2008 Messages 465 Gender Male HSC 2010 Apr 17, 2010 #6 wow nice question, even had partial fractions in there, great job shaono