- #1
yxgao
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What is the frequency of SMALL oscillations about è[t] = 0 of the following expression: Assume that w t is a constant.
A Cos[w t - è[t]] + B è''[t]==0, where A and B are arbitrary constants?
If you expand the Cosine term, you get A Cos[w t] Cos[è[t]] + A Sin[w t] Sin[è[t]] +B è''[t] ==0, which can be approximated as:
B è''[t] + A Sin[w t] è[t]== -A Cos[w t]
So is the frequency of small oscillations just Sqrt[(A Sin[w t])/B]?
A Cos[w t - è[t]] + B è''[t]==0, where A and B are arbitrary constants?
If you expand the Cosine term, you get A Cos[w t] Cos[è[t]] + A Sin[w t] Sin[è[t]] +B è''[t] ==0, which can be approximated as:
B è''[t] + A Sin[w t] è[t]== -A Cos[w t]
So is the frequency of small oscillations just Sqrt[(A Sin[w t])/B]?