Question

If f(t) = u(t), then its Laplace transform is?

(a) \(\frac{scos(b)-asin(b)}{s^2+a^2}\)

(b) 1/2

(c) \(\frac{s}{s^2-a^2}\)

(d) \(\frac{b}{(s-a)^2+b^2}\)

The question was posed to me in a job interview.

I need to ask this question from Existence and Laplace Transform of Elementary Functions topic in section Laplace Transform of Engineering Mathematics

Answer 1

Correct answer is (b) 1/2

The best I can explain: The Laplace transform of a function is given by

\(\{f(t)\}=F(s)=\int_0^{\infty} f(t)e^{-st}dt\)

put f(t) = u(t) to solve the problem.