Differential Equation - Where am I going wrong?

[oneamp]

Homework Statement

Using Euler's Method:

a) Find the approximate values of the solution of the given initial value problem at t = 0.1, 0.2, 0.3, and 0.4 using the Euler method with h= 0.1

b) Repeat part (a) with h = 0.05.

I am doing part (b). The function is y' = 0.5 - t + 2y, y(0)=1

Homework Equations

For Euler's Method:
y_n = y_n-1 + h * F(x_n-1, y_n-1)

The Attempt at a Solution

I've done it according to the book, using Euler's Method. I am trying to find y_1 but am not coming up with the book answer, for (b).

h = 0.05
so t = 0.05, 0.10, 0.15, 0.20 (but not interested in these yet, just want y_1 to be right!)


y_1 = 1 + (0.05) [0.5 - 0 + (2)(1)]
should be 1.26, but I get the wrong answer. What am I doing wrong? :(

Thanks

 

[Office_Shredder]

I think you have the correct formula for y₁. I will observe that y₂, which is your approximation for y(.1), is in fact 1.26 if you take the next step. You are simply confusing what you're supposed to be comparing to your answer sheet.

 

[oneamp]

Thank you!