how to define a variable as a function of another variable in symbolic toolbox
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Hi I am just wondering whether is it possible to do following: define a variable as a function of x
u=f(x)
Then,
d/dx (u*x) = u'x + xu'
u' is first derivative of u w.r.t. x.
Is this possible to do using matlab symbolic toolbox?
2 个评论
Star Strider
2014-10-6
You need to set it up correctly:
syms f(x) u(x)
ddx = diff(u*f,x)
—>
ddx(x) =
D(f)(x)*u(x) + f(x)*D(u)(x)
回答(1 个)
Azzi Abdelmalek
2014-10-5
syms x u
u=cos(x)
y=u*x
out=diff(y,x)
3 个评论
Star Strider
2014-10-6
You need to set it up correctly:
syms f(x) u(x)
ddx = diff(u*f,x)
—>
ddx(x) =
D(f)(x)*u(x) + f(x)*D(u)(x)
另请参阅
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