t = var('t')
R = vector ((3*cos(t), 3*sin(t), 4*t))
dRdt = R.diff(t)
show(dRdt)
ds = dRdt.norm()
show(ds)
when I try to show ds it gives mi a trigonometric expression which is actually is equal to 5. I tried simplify() and trig_simplify but it didn't help...
Any tips are welcome. Thanks in advance
Well...
sage: R=vector([3*cos(t),3*sin(t),4*t]);R
(3*cos(t), 3*sin(t), 4*t)
sage: with assuming(t,"real"): (R.diff(t).norm()^2).trig_reduce().sqrt()
5
or even :
sage: with assuming(t,"real"): R.diff(t).norm().trig_reduce()
5
Is that acceptable to you ?
Asked: 2018-04-12 19:13:32 +0100
Seen: 711 times
Last updated: Apr 12 '18
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