## allyfranken Suppose L is the operator defined by Ly=D2y−3Dy+y. Compute L(sin(x)). one year ago one year ago

1. vf321

Well do you know the 2nd and 1st derivative of sin?

2. allyfranken

yeah

3. vf321

Well then, what's $$D^2_x \sin x$$ and $$D_x \sin x$$?

4. allyfranken

-sin(x) and cos(x)

5. allyfranken

so would my answer be: -sin(x) - 3cos(x) + sin(x)?

6. vf321

yes

7. allyfranken

wow that was way easier than i thought, thank you!

8. vf321

Yeah, the hard part is taking the laplace transform of it!