## 50 Reputation

5 years, 283 days

## @Carl Love  my solution was: T := ...

my solution was:

T := OuterProductMatrix(U, U);
z1 := diff(T[1, 1], x)+diff(T[1, 2], y)+diff(T[1, 3], z);
z2 := diff(T[2, 1], x)+diff(T[2, 2], y)+diff(T[2, 3], z);
z3 := diff(T[3, 1], x)+diff(T[3, 2], y)+diff(T[3, 3], z);
V2 := convert([z1, z2, z3], Vector[column]);

but yours more elegant.

Thanks!

## Thanks you guys. Both answers helped me ...

Thanks you guys. Both answers helped me alot!

## thank you guys for your awesome support!...

thank you guys for your awesome support!!

## @Markiyan Hirnyk  thats true. But I...

thats true. But I had to improve my model equation. Do to the added "cos(diff(h(t), t))" right side of the equation it isnt possible to solve the equation for "diff(h(t), t)" before I run the solver

## @nm  yes your right. I though it wo...

yes your right. I though it would improve the readability this way. But here is the plain code:

ODE := A*(diff(h(t), t))^2+B*(diff(h(t), t))*(h(t)+C)+E*h(t) = F*cos(diff(h(t), t))
ODE_SOLUTION := dsolve({ODE, h(0) = 0}, numeric, range = 0 .. 10, parameters = [A, B, C, E, F])

## Thanks to both of you!   Now my opt...

Thanks to both of you!

Now my optimizations works as expected!