Is my unit step function correct for solving this differential equation?

gbuitkus
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Homework Statement


y''-4y'-32y={1 when 0<=t<1 and 0 when 1<=t
y(0)=y'(0)=0


Homework Equations





The Attempt at a Solution


s2L(y) -4sL(y)-32 L(y)=u1(t)

I am just struggling to figure out if my unit step function is correct.

Solving for L(y) I get:
(e-s) / (s(s2 -4s-32))
but it says I am wrong so I am pretty sure I am doing something wrong with the unit step function
 
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gbuitkus said:

Homework Statement


y''-4y'-32y={1 when 0<=t<1 and 0 when 1<=t
y(0)=y'(0)=0

Homework Equations


The Attempt at a Solution


s2L(y) -4sL(y)-32 L(y)=u1(t)

I am just struggling to figure out if my unit step function is correct.

Solving for L(y) I get:
(e-s) / (s(s2 -4s-32))
but it says I am wrong so I am pretty sure I am doing something wrong with the unit step function

You didn't explain what your notation ##u_1(t)## means. Is it ##u(t-1)##? What you want on the right side is ##u(t)-u(t-1)##.
 
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