# Question:dsolve problems

## Question:dsolve problems

`I tried to solve the system of odinary differential equations. But system was not able to solve it. As a result i've obtained a error message displayed on the last line of my program. Give me advise please how to overcome this problem.`
`restart; unprotect(gamma); gamma := 1.322; m0 := 0.759e-22*0.1e-2; d[1] := 0.1e-2; d[2] := 0.2e-1; A[1] := (1/4)*Pi*d[1]^2; A[2] := (1/4)*Pi*d[2]^2; k[B] := 0.138e-22; T[res] := 300; kp := 0.1e6*(1/760); P[res] := (20*760)*kp; V[1] := 0.25133e-3; V[2] := 0.25133e-2; U[p] := 0.6664e-2; a := U[p]/V[2]; alpha[1] := k[B]*T[res]*(`#msub(mi("N"),mo("in",fontweight = "bold"))`(t)-N[out](t))/V[1]; P[1] := P[res]*(alpha[1]/P[res])^gamma; T[1] := T[res]*(P[1]/P[res])^((gamma-1)/gamma); alpha[2] := k[B]*T[1]*(N[out](t)-N[pump](t))/V[2];sys := diff(`#msub(mi("N"),mo("in",fontweight = "bold"))`(t), t) = evalf(simplify(A[1]*sqrt(gamma*(2/(gamma+1))^((gamma+1)/(gamma-1))*P[res]^2*(1-(alpha[1]/P[res])^gamma)/(k[B]*T[res]*m0)))), diff(N[out](t), t) = evalf(A[2]*sqrt(gamma*(2/(gamma+1))^((gamma+1)/(gamma-1))*P[1]^2*(1-(alpha[2]/P[1])^gamma)/(k[B]*T[1]*m0))), diff(N[pump](t), t) = a*(N[out](t)-N[pump](t));ics := `#msub(mi("N"),mo("in",fontweight = "bold"))`(0) = 0, N[pump](0) = 0., N[out](0) = 0;dsn1 := dsolve([sys, ics], numeric, method = ck45, output = listprocedure, range = 0 .. 100);`
`Error, (in f) unable to store 'HFloat(HFloat(undefined))+HFloat(HFloat(undefined))*I' when datatype=float[8]`
`Edit: to fix formatting problems`
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