# Question:How do i solve this problem?(Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations)

## Question:How do i solve this problem?(Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations)

Maple 2022

restart;
with(plots);
with(plottools);
with(DEtools);
N := S(t) + In(t) + C(t);
N := S(t) + In(t) + C(t)

eqn1 := diff*(S(t), t) = lambda - (lambda + sigma)*S(t) - (beta + Zeta)*S(t)*In(t) - beta[1]*S(t)*C(t), S(0) = ic1;
eqn1 := diff (S(t), t) = lambda - (lambda + sigma) S(t)

- (beta + Zeta) S(t) In(t) - beta[1] S(t) C(t), S(0) = ic1

eqn2 := diff*(In(t), t) = beta*S(t)*In(t) - (lambda + gamma)*In(t), In(0) = ic2;
eqn2 :=

diff (In(t), t) = beta S(t) In(t) - (lambda + gamma) In(t),

In(0) = ic2

eqn3 := diff*(C(t), t) = Zeta*In(t) + Zeta*In(t)^2 - (rho + lambda)*C(t) - Zeta*C(t)*In(t), C(0) = ic3;
2
eqn3 := diff (C(t), t) = Zeta In(t) + Zeta In(t)

- (rho + lambda) C(t) - Zeta C(t) In(t), C(0) = ic3

lambda := 0.117852;
lambda := 0.117852

mu := 0.035378;
mu := 0.035378

beta := 0.11;
beta := 0.11

beta__1 := 0.05;
beta__1 := 0.05

g := 1;
rho := 0.1;
rho := 0.1

zeta := 0.02;
zeta := 0.02

sigma := 0.066;
sigma := 0.066

ic1 := 2390000;
ic2 := 753;
ic4 := 358500;
ic1 := 2390000

ic2 := 753

ic4 := 358500

dsol := dsolve([eqn1, eqn2, eqn3], numeric);
Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

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