LAPLACE TRANSFORMATIONS !!!!!


A technique of solving diffential equations deals with the Laplace Transformations of a function.

Let ƒ(t) be a function of 't' defined for all +ve values of t , then 0∫∞ e - st ƒ(t) dt ; is called the Laplace transforms of ƒ(t) , provided the integral exists.

's' is a parameter which may be real or, a complex number.

It is denoted by L{Æ’(t)} or Æ’(s).

I don't know the answers,so pls post the soln. as well.

8 Answers

11
rkrish ·


Q1. If L{Æ’(t)} = Æ’(s) , then L{t10 e - at} =

(A) 9 ! ∀ s > - a (B) 10 ! ∀ s > a
(s+a)10 (s+a)11

(C) 10 ! ∀ s > - a (D) 11 ! ∀ s > a
(s+a)11 (s+a)11

11
rkrish ·


Q2. If L{Æ’(t)} = Æ’(s) , then L{t4 Æ’(t)} =

(A) s4 . Æ’(s) (B) - s4 . Æ’(s)

(C) d4 (Æ’(s)) (D) - d4 (Æ’(s))
ds4 ds4

11
rkrish ·


Q3. If L{ƒ(t)} = ƒ(s) , then L{ 0∫t ƒ(u) du } =

(A) Æ’(s) / s for all s (B) Æ’(s) / s for all s > 0

(C) s . Æ’(s) for all s (D) s . Æ’(s) for all s > 0

11
Mani Pal Singh ·

lapace laws are not in JEE syllabus

1
MATRIX ·

[1][1][1]..........hmmm.......

1
MATRIX ·

[9][9][9]........mani always says this is not in JEE syllabus :P...

11
Mani Pal Singh ·

Nahin yaar sacchi
Its IIT JEE not a mazak
i dont know about ur institute [7]
SO BETTER NOT TO WORRY ABOUT IT SO MUCH AND FOCUS ON SOMETHING WHICH IS IN THE SYLLABUS

24
eureka123 ·

well well well.......plz dont take this personally rkrish........

but all the so called test series and practice tests are just for name...the reality is that it is sheer marketing and business....big institutes put unwanted things in these tests which are miles away from JEE.............they do these cheap things just to show their institute's high standards and the intelligence of their professors..........but it is upto us to understand what to concentrate upon and what not to.......

coming to ur question laplace transformations is 1000% not in JEE.......

so my sincere advice would be not to waste ur precious time over them unless you are in class 11....where u can enjoy these adventures[1][1]

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