# Laplace transform 1 marks

GATE 2017 Set-2

1. The Laplace transform of tet is

(A) $$\large \frac{s}{(s+1)^2}$$

(B) $$\large \frac{1}{(s-1)^2}$$

(C) $$\large \frac{1}{(s+1)^2}$$

(D) $$\large \frac{s}{(s-1)}$$

GATE 2016 Set-1

1. If f(t) is a function defined for all t ≥ 0, its Laplace transform F(s) is defined as

(A)$$\large \int_{0}^{\infty}e^{st}f(t)dt$$

(B)$$\large \int_{0}^{\infty}e^{-st}f(t)dt$$

(C)$$\large \int_{0}^{\infty}e^{ist}f(t)dt$$

(D)$$\large \int_{0}^{\infty}e^{-ist}f(t)dt$$

GATE 2016 Set-2

1. Laplace transform of cos(ωt) is

(A) $$\large \frac{s}{s^2+\omega ^2}$$

(B)$$\large \frac{\omega}{s^2+\omega ^2}$$

(C)$$\large \frac{s}{s^2-\omega ^2}$$

(D)$$\large \frac{\omega}{s^2-\omega ^2}$$

GATE 2016 Set-3

1. Solutions of Laplace’s equation having continuous second-order partial derivatives are called

(A) biharmonic functions

(B) harmonic functions

(C) conjugate harmonic functions

(D) error functions

GATE 2015 Set-2

1. The Laplace transform of ei5t where i=√-1, is

(A)$$\large \frac{s-5i}{s^2-25}$$

(B)$$\large \frac{s+5i}{s^2+25}$$

(C)$$\large \frac{s+5i}{s^2-25}$$

(D)$$\large \frac{s-5i}{s^2+25}$$

GATE 2009

1. The inverse Laplace transform of $$\large \frac{1}{(s^2+s)}$$ is

(A) $$\large 1+e^t$$

(B) $$\large 1-e^t$$

(C) $$\large 1-e^{-t}$$

(D) $$\large 1+e^{-t}$$