Skip to main content
edited title
Link

Can I combine the backward and forward euler methods - simialr to modified euler method?

Source Link

Can I combine the backward and forward euler methods simialr to modified euler method?

Constructing Modified Euler

Using the same strategy as done in the construction of Modified Euler. Starting from Trapezoidal Method $$y_1 = y_0 + \dfrac{h}{2}\left(f(x_0,y_0) + f(x_1,y_1)\right)$$ then approximating $f(x_1,y_1)$ using the explicit euler $y_1 = y_0 + hf(x_0,y_0)$ , thereby constructing the modified euler method $$y_1 = y_0 + \dfrac{h}{2}\left(f(x_0,y_0) + f(x_1,y_0 + hf(x_0,y_0))\right)$$

This is a valid method that is often seen in most textbooks.


New Method: Combining both backward and forward Euler methods

However, I wanted to ask why haven't I seen a similar approach done for the backward euler?

starting with the implicit euler:
$$y_1 = y_0 + hf(x_1,y_1)$$

then using the same approach as before, we can replace $y_1$ $$y_1 = y_0 + hf(x_1,y_0 + hf(x_0,y_0))$$

Come to think of it, maybe it is not used because it defeats the purpose of the implicit euler method. But I am not sure if this really the case. And, Is this even consistent?

I was thinking that it may be equivalent to some other method, and I should look for its equivalent RK-Method/Butcher Tableau?