# Derive 6

1. May 18, 2008

### gtfitzpatrick

i'm not sure if this is the right place but i'm trying to get my head around derive 6 and i have a couple of questions that dont seem to be coming out right...

d$$^{2}$$y/dx$$^{2}$$ + 8dy/dx + 16y = (4e$$^{-4x}$$)(sinx+cosx)$$^{2}$$ ; y(0)=y'(0)=0

so i inputed DSOLVE2_BV(8, 16, (4·^(- 4·x))·(SIN(x) + COS(x)) ∧ 2, x, 0, 0)

but its not throwing up the right answer?

2. May 18, 2008

### Defennder

Are you doing this by hand or computer? If you're solving it by hand, note that the variation of parameters works here; only problem is that the integrals you have to solve for the particular solutions can be rather difficult, though doable.

3. May 19, 2008

### gtfitzpatrick

trying by computer, using a program called derive