(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

angle [0,2Pi] from bottom most position, find the 2nd order nonlinear ODE for evolution of the pendulum in terms of angle

then assume angle is small, do the linear approximation to the equation

2. Relevant equations

use balance of forces and newton's 2nd law

3. The attempt at a solution

y''+g*siny\L = 0 but then how to find the linear approximation about y'' + g*y\L=0

i tried, by the formula, y = C1*cos(i*sqrt(g\L)t) + C2*sin(i*sqrt(g\L)t)

Is that correct? Thanks a lot~

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# Homework Help: Ask help about the pendulum~ THX

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