Actually, the ode system is a part of an optimal control problem and I need the symbolic solution based on σ1 and σ2.

Thanks.

@Carl Love 

After eliminating t[f] the problem was solved.

optimal.mw@Carl Love 

Here you are the worksheet. thanks.

@Carl Love

sometimes the map works and sometimes does not.

I am confused, can you help me. Thanks a lot.

@Carl Love 

Thank you very much. with 'map' the problem was solved.

optimal.mw@Carl Love 

@Carl Love 

pantograph2.mw

@Markiyan Hirnyk