Number theory and matrices

[james_j966]

hi everyone,

i am currently stuck on a maths question for my engineering course and was wondering if there was someone who could help explain how to get the answer;


"A damped oscillation of a system is given by the equation:

y = -7.4e0.5t sin 3t.

Determine the value of t near to 4.2, correct to3 significant figures, when the magnitude y of the oscillation is zero, using both the bisection method and Newton Raphson method."


thank you for any help.
James

 

[HallsofIvy]

So you want to solve the equation -7.4e^(0.5t) sin(3t)= 0 "using both the bisection method and the Newton-Raphson method"? Do you know what those methods are? If so why haven't you started? If not why haven't you looked them up?

Frankly, I don't see why you would need numerical methods, An exponential is never 0 so we can immediately divide by -7.4 e^(0.5t) leaving just sin(3t)= 0. The problem is that, while that equation has infinitely many solutions, none of them are "near 4.2".

Oh, and you titled this thread "Number Theory and Matrices" but I see no mention of either in this problem. Are you sure you have copied the problem correctly?

 

[Deleted member 4993]

hi everyone,

i am currently stuck on a maths question for my engineering course and was wondering if there was someone who could help explain how to get the answer;


"A damped oscillation of a system is given by the equation:

y = -7.4e0.5t sin 3t.

Determine the value of t near to 4.2, correct to3 significant figures, when the magnitude y of the oscillation is zero, using both the bisection method and Newton Raphson method."


thank you for any help.
James

\(\displaystyle y = -7.4 * e^{0.5t}* sin (3t)\) ..... does not LOOK LIKE a solution for "damped" system! Did you copy the problem correctly?

You have NOT answered the questions posed in ... https://www.freemathhelp.com/forum/...or-differential-equations.122807/#post-496249