(adsbygoogle = window.adsbygoogle || []).push({});

:surprise:

Hello,

I've to calculate the derivate of :

[tex]

\displaystyle \sigma_{N}(t):=\sum_{i=1}^{N}g_{i}(t)

[/tex]

and [tex] g_{i}(t) [/tex] verify the differential equation:

[tex] \displaystyle \frac{d g_i}{d t}(t) =

\sum_{k=1}^{i-1} \frac{1}{k}K(k,i-k) g_{i-k}(t) g_k(t) - \sum_{l=1}^{\infty} \frac{1}{l}K(l,i) g_i(t)g_l(t) [/tex].

I've to justify:

[tex] \displaystyle \partial_{t}\sigma_{N}(t):= - \sum_{i,j\leqN;i+j>N}\frac{1}{j}K(j,i) g_i(t)g_l(t) [/tex]

Thanks.

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Calculate the derivate

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

Loading...

Similar Threads - Calculate derivate | Date |
---|---|

B Calculate probability of getting 2 red balls | Mar 2, 2018 |

I How to calculate the tractive effort of a train? | Feb 27, 2018 |

I Weights and interpolation -- Replicating Python code with hand calculations | Feb 16, 2018 |

How does the Kalman filter calculate derivatives? | Jul 22, 2015 |

How does a TI-84 calculate the derivative at a point? | Apr 15, 2009 |

**Physics Forums - The Fusion of Science and Community**