Can't get integration right - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: General Forum (/forum-4.html) +--- Thread: Can't get integration right (/thread-6328.html) Can't get integration right - Marcio - 05-31-2016 12:16 PM Hello all, Would you be king enough as to point out what I am doing wrong with this very simple integration? $t = \int_0^{0.515}\frac{1}{0.000273\times exp\left[16306\times\left(\frac{1}{535}-\frac{1}{535+90.45x}\right)\right](1-x)} dx$ The correct answer is $$833$$ but I keep getting $$838.867\pm2.38E-7$$ with FIX 9. This is the code I am using on the 15C: R0 = 0.000273 R1 = 16306 R2 = 535 R3 = 90.45 Code: LBL 0 RCL 3 x RCL 2 + CHS 1/X RCL 2 1/X + RCL 1 x exp RCL 0 x x<>y CHS 1 + x 1/X RTN Very much appreciated. RE: Can't get integration right - Werner - 05-31-2016 12:36 PM You're not doing anything wrong, as that is the correct answer for the problem as stated. Perhaps a digit is wrong somewhere in the constants? Werner RE: Can't get integration right - Marcio - 05-31-2016 01:39 PM That is right. Just found out 833 was a "close" approximation and 838.87 is actually the correct answer. Thank you.