The Laplace transform of f(t) = sin πt is $$F\left( s \right) = \frac{\pi }{{{s^2}\left( {{s^2} + {\pi ^2}} \right)}},\,s > 0.$$ Therefore, the Laplace transform of t sin πt is
A finite wave train, of an unspecified nature, propagates along the positive X-axis with a constant speed v and without any change of shape. The differential equation among the four listed below, whose solution it must be, is
Which of the following vectors is orthogonal to the vector \[\left( {a\hat i + b\hat j} \right),\] where a and b (a ≠ b) are constants, and \[{\hat i}\] and \[{\hat j}\] are unit orthogonal vectors?