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derm
laplace unit step function (t-4)???
What exactly is your question?
If you need some general help understanding it and how it used, you might find this lecture helpful: http://ocw.mit.edu/courses/mathematics/18-03-differential-equations-spring-2010/video-lectures/lecture-22-using-laplace-transform-to-solve-odes-with-discontinuous-inputs/
laplace the equation....actually the equation given is unit step function..as 91 typing...could u understand me?
and also how to laplace this one(t-4/(4))
I recommend you watch the lecture. He will explain that for you.