# Differential equations – How do you solve these ODEs with NDSolve?

The calculation changes `t = 0` there `sin[ψ`

``` eq1 = ω1 eq2 = ω2 and construct the linear combinations, eq1n = Simplify[eq1Sin[eq1Sin[eq1Sin[eq1Sin[ψ (* Cos[ψ (If this were not possible, the equations themselves could not be solved in principle.) Now replace eq1, eq2 by eq1n, eq2n, I1 = 2; I2 = 3; I3 = 4; s = NDSolveValue[{I1*ω1&#39;[{I1*ω1'[{I1*ω1'[{I1*ω1' I2 * ω2 & # 39; I3 * ω3 & # 39; eq1n == 0, eq2n == 0, ω3 ω1 == 2, ω2 == 3, ω3 == 4, ψ == 0, φ == 0, θ == Pi / 6}, {ω1 plot[Evaluate@s[[1 ;; 3]], {t, 0, 120}, ImageSize -> Large]plot[Evaluate@s[[4 ;; 6]], {t, 0, 120}, ImageSize -> Large]  Incidentally, the original equations can be solved by slightly changing the initial state ψ == 0 to ψ == 10 ^ -6, Another approach is to use the option. Method -> {"EquationSimplification" -> "Residual"} Everyone gives the same answer. ```
``` ```
``` Author AdminPosted on March 17, 2019Categories ArticlesTags differential, equations, NDSolve, ODEs, solve ```
``` Post navigation Previous Previous post: Is White Supremacy a Global Terrorist Threat?Next Next post: Lightning Network – I can pay bills on my Mainnet LND node, but others can not pay my bills ```