Question: Computing the left and right eigenvectors

Someone please help me with the computation of the right and left eigenvectors. my system of equation is attached below

with(VectorCalculus):

 

interface(imaginaryunit = I)

I

(2)

I

I

(3)

sqrt(-4)

2*I

(4)

NULL

``

Limit(N(t) = N__0*exp(-mu*t)+exp(mu*t)*K/mu, t = infinity)

 

limit(N(t), t = infinity) = limit(N__0*exp(-mu*t)+exp(mu*t)*K/mu, t = infinity)

(5)

 

NULL

#to calculate the  disease free equilibrium,

NULL

E1 := -S*µ__C+`Λ__p`

-S*µ__C+Lambda__p

(6)

NULL

``

(7)

E3 := -S__A*µ__A+`Λ__A`

-S__A*µ__A+Lambda__A

(8)

NULL

``

(9)

NULL

``

(10)

NULL

solve({E1 = 0, E3 = 0}, {S, S__A})

{S = Lambda__p/µ__C, S__A = Lambda__A/µ__A}

(11)

NULL

NULL#to calculate the Endemic Equilibrium state,

Typesetting:-mparsed()

(12)

restart

with(VectorCalculus):

 

interface(imaginaryunit = I)

I

(14)

I

I

(15)

sqrt(-4)

2*I

(16)

``

E1 := `Λ__p`-(`ϕ`*`θ__B`*I__A/N__p+µ__C)*S+`ω__B`*I__B

Lambda__p-(varphi*theta__B*I__A/N__p+µ__C)*S+omega__B*I__B

(17)

E2 := `ϕ`*`θ__B`*I__A*S/N__p-`ω__B`*I__B-(`σ__B`+µ__C)*I__B

varphi*theta__B*I__A*S/N__p-omega__B*I__B-(sigma__B+µ__C)*I__B

(18)

``

(19)

E3 := `Λ__A`-(µ__A+`ϕ`*`α__B`*I__B/N__p)*S__A+`δ__A`*I__A

Lambda__A-(µ__A+varphi*alpha__B*I__B/N__p)*S__A+delta__A*I__A

(20)

E4 := `ϕ`*`α__B`*I__B*S__A/N__p-(µ__A+`δ__A`)*I__A

varphi*alpha__B*I__B*S__A/N__p-(µ__A+delta__A)*I__A

(21)

NULL

``

(22)

NULL

``

(23)

solve({E1 = 0, E2 = 0, E3 = 0, E4 = 0}, {I__A, I__B, S, S__A})

{I__A = 0, I__B = 0, S = Lambda__p/µ__C, S__A = Lambda__A/µ__A}, {I__A = -(N__p^2*µ__A^2*µ__C^2+N__p^2*µ__A^2*µ__C*omega__B+N__p^2*µ__A^2*µ__C*sigma__B+N__p^2*µ__A*µ__C^2*delta__A+N__p^2*µ__A*µ__C*delta__A*omega__B+N__p^2*µ__A*µ__C*delta__A*sigma__B-varphi^2*Lambda__A*Lambda__p*alpha__B*theta__B)/(varphi*µ__A*theta__B*(N__p*µ__A*µ__C+N__p*µ__A*sigma__B+N__p*µ__C*delta__A+N__p*delta__A*sigma__B+varphi*Lambda__p*alpha__B)), I__B = -(N__p^2*µ__A^2*µ__C^2+N__p^2*µ__A^2*µ__C*omega__B+N__p^2*µ__A^2*µ__C*sigma__B+N__p^2*µ__A*µ__C^2*delta__A+N__p^2*µ__A*µ__C*delta__A*omega__B+N__p^2*µ__A*µ__C*delta__A*sigma__B-varphi^2*Lambda__A*Lambda__p*alpha__B*theta__B)/(alpha__B*(N__p*µ__A*µ__C^2+N__p*µ__A*µ__C*omega__B+N__p*µ__A*µ__C*sigma__B+varphi*µ__C*Lambda__A*theta__B+varphi*Lambda__A*sigma__B*theta__B)*varphi), S = (N__p*µ__A*µ__C+N__p*µ__A*sigma__B+N__p*µ__C*delta__A+N__p*delta__A*sigma__B+varphi*Lambda__p*alpha__B)*µ__A*N__p*(µ__C+omega__B+sigma__B)/(alpha__B*varphi*(N__p*µ__A*µ__C^2+N__p*µ__A*µ__C*omega__B+N__p*µ__A*µ__C*sigma__B+varphi*µ__C*Lambda__A*theta__B+varphi*Lambda__A*sigma__B*theta__B)), S__A = N__p*(N__p*µ__A^2*µ__C^2+N__p*µ__A^2*µ__C*omega__B+N__p*µ__A^2*µ__C*sigma__B+N__p*µ__A*µ__C^2*delta__A+N__p*µ__A*µ__C*delta__A*omega__B+N__p*µ__A*µ__C*delta__A*sigma__B+varphi*µ__A*µ__C*Lambda__A*theta__B+varphi*µ__A*Lambda__A*sigma__B*theta__B+varphi*µ__C*Lambda__A*delta__A*theta__B+varphi*Lambda__A*delta__A*sigma__B*theta__B)/(varphi*µ__A*theta__B*(N__p*µ__A*µ__C+N__p*µ__A*sigma__B+N__p*µ__C*delta__A+N__p*delta__A*sigma__B+varphi*Lambda__p*alpha__B))}

(24)

``

J := Jacobian([E1, E2, E3, E4], [S, I__B, S__A, I__A])

Matrix(%id = 18446746854857131062)

(25)

NULL

restart

J := Matrix(4, 4, {(1, 1) = -`ϕ`*`θ__B`*I__A/N__p-µ__C, (1, 2) = `ω__B`, (1, 3) = 0, (1, 4) = -`ϕ`*`θ__B`*S/N__p, (2, 1) = `ϕ`*`θ__B`*I__A/N__p, (2, 2) = -`ω__B`-`σ__B`-µ__C, (2, 3) = 0, (2, 4) = `ϕ`*`θ__B`*S/N__p, (3, 1) = 0, (3, 2) = -`ϕ`*`α__B`*S__A/N__p, (3, 3) = -µ__A-`ϕ`*`α__B`*I__B/N__p, (3, 4) = `δ__A`, (4, 1) = 0, (4, 2) = `ϕ`*`α__B`*S__A/N__p, (4, 3) = `ϕ`*`α__B`*I__B/N__p, (4, 4) = -µ__A-`δ__A`})

Matrix(%id = 18446746579340105118)

(26)

S := `Λ__p`/µ__C

Lambda__p/µ__C

(27)

S__A := `Λ__A`/µ__A

Lambda__A/µ__A

(28)

I__B := 0

0

(29)

I__A := 0

0

(30)

NULL

0

(31)

J := Matrix(4, 4, {(1, 1) = -`ϕ`*`θ__B`*I__A/N__p-µ__C, (1, 2) = `ω__B`, (1, 3) = 0, (1, 4) = -`ϕ`*`θ__B`*S/N__p, (2, 1) = `ϕ`*`θ__B`*I__A/N__p, (2, 2) = -`ω__B`-`σ__B`-µ__C, (2, 3) = 0, (2, 4) = `ϕ`*`θ__B`*S/N__p, (3, 1) = 0, (3, 2) = -`ϕ`*`α__B`*S__A/N__p, (3, 3) = -µ__A-`ϕ`*`α__B`*I__B/N__p, (3, 4) = `δ__A`, (4, 1) = 0, (4, 2) = `ϕ`*`α__B`*S__A/N__p, (4, 3) = `ϕ`*`α__B`*I__B/N__p, (4, 4) = -µ__A-`δ__A`})

Matrix(%id = 18446746579340107518)

(32)

J := Matrix(4, 4, {(1, 1) = -µ__C, (1, 2) = `ω__B`, (1, 3) = 0, (1, 4) = -`β__1`, (2, 1) = 0, (2, 2) = -`ω__B`-`σ__B`-µ__C, (2, 3) = 0, (2, 4) = -`β__1`, (3, 1) = 0, (3, 2) = -`β__2`, (3, 3) = -µ__A, (3, 4) = `δ__A`, (4, 1) = 0, (4, 2) = `β__2`, (4, 3) = 0, (4, 4) = -µ__A-`δ__A`})

Matrix(%id = 18446746579417403630)

(33)

"simplify( ? )"

Matrix(%id = 18446746579305905318)

(34)

"LinearAlgebra:-Eigenvalues( ? )"

Vector[column](%id = 18446746579445964182)

(35)

"LinearAlgebra:-CharacteristicPolynomial( ?, lambda )"

lambda^4+(2*µ__A+delta__A+omega__B+sigma__B+2*µ__C)*lambda^3+(beta__1*beta__2+µ__A^2+4*µ__A*µ__C+µ__A*delta__A+2*µ__A*omega__B+2*µ__A*sigma__B+µ__C^2+2*µ__C*delta__A+µ__C*omega__B+µ__C*sigma__B+delta__A*omega__B+delta__A*sigma__B)*lambda^2+(beta__1*beta__2*µ__A+beta__1*beta__2*µ__C+2*µ__A^2*µ__C+µ__A^2*omega__B+µ__A^2*sigma__B+2*µ__A*µ__C^2+2*µ__A*µ__C*delta__A+2*µ__A*µ__C*omega__B+2*µ__A*µ__C*sigma__B+µ__A*delta__A*omega__B+µ__A*delta__A*sigma__B+µ__C^2*delta__A+µ__C*delta__A*omega__B+µ__C*delta__A*sigma__B)*lambda+beta__1*beta__2*µ__A*µ__C+µ__A^2*µ__C^2+µ__A^2*µ__C*omega__B+µ__A^2*µ__C*sigma__B+µ__A*µ__C^2*delta__A+µ__A*µ__C*delta__A*omega__B+µ__A*µ__C*delta__A*sigma__B

(36)

NULL

"(->)"

Vector[column](%id = 18446746579340117046)

(37)

# to find the trace we

 

Matrix(7, 7, {(1, 1) = -beta*lambda-v__1-µ, (1, 2) = v__2, (1, 3) = 0, (1, 4) = 0, (1, 5) = 0, (1, 6) = 0, (1, 7) = 0, (2, 1) = v__1, (2, 2) = beta*(w-1)*lambda-µ-v__2-alpha, (2, 3) = 0, (2, 4) = 0, (2, 5) = 0, (2, 6) = 0, (2, 7) = 0, (3, 1) = 0, (3, 2) = alpha, (3, 3) = -µ, (3, 4) = 0, (3, 5) = `ρ__A`, (3, 6) = `ρ__F`, (3, 7) = -(-1+k)*`ρ__Q`, (4, 1) = beta*lambda, (4, 2) = -beta*(w-1)*lambda, (4, 3) = 0, (4, 4) = -q__E-delta-µ, (4, 5) = 0, (4, 6) = 0, (4, 7) = 0, (5, 1) = 0, (5, 2) = 0, (5, 3) = 0, (5, 4) = a*delta, (5, 5) = -`ρ__A`-q__A-µ, (5, 6) = 0, (5, 7) = k*`ρ__Q`, (6, 1) = 0, (6, 2) = 0, (6, 3) = 0, (6, 4) = -delta*(-1+a), (6, 5) = 0, (6, 6) = -`ρ__F`-q__F-`δ__F`-µ, (6, 7) = 0, (7, 1) = 0, (7, 2) = 0, (7, 3) = 0, (7, 4) = q__E, (7, 5) = q__A, (7, 6) = q__F, (7, 7) = -`ρ__Q`-`δ__Q`-µ})

Matrix(%id = 36893490965935089652)

(38)

"(->)"

-beta*lambda-v__1-7*µ+beta*(w-1)*lambda-v__2-alpha-q__E-delta-rho__A-q__A-rho__F-q__F-delta__F-rho__Q-delta__Q

(39)

 

#this shows that trace is negative

 

#to Achieve stability, the value below must be less than zero

 

(-q__E-delta-µ)*(-`&rho;__F`-q__F-`&delta;__F`-µ)*(-k*q__A*`&rho;__Q`+q__A*µ+q__A*`&delta;__Q`+q__A*`&rho;__Q`+µ^2+µ*`&delta;__Q`+µ*`&rho;__A`+µ*`&rho;__Q`+`&delta;__Q`*`&rho;__A`+`&rho;__A`*`&rho;__Q`)*µ < 0

(-q__E-delta-µ)*(-rho__F-q__F-delta__F-µ)*(-k*q__A*rho__Q+q__A*rho__Q+q__A*µ+q__A*delta__Q+rho__A*rho__Q+rho__A*µ+rho__A*delta__Q+rho__Q*µ+µ^2+µ*delta__Q)*µ < 0

(40)

 NULL

M := diff(N(t), t) = Pi-µ*N(t)

diff(N(t), t) = Pi-µ*N(t)

(41)

dsolve({M}, N(t))

{N(t) = Pi/µ+exp(-µ*t)*_C1}

(42)

eval({N(t) = Pi/µ+exp(-µ*t)*_C1}, [t = infinity])

{N(infinity) = Pi/µ+exp(-µ*infinity)*_C1}

(43)

value(%)

{N(infinity) = Pi/µ+exp(-µ*infinity)*_C1}

(44)

Limit(N(t) = Pi/µ+exp(-µ*t)*_C1, t = infinity); value(%)

Limit(N(t) = Pi/µ+exp(-µ*t)*_C1, t = infinity)

 

limit(N(t), t = infinity) = limit(Pi/µ+exp(-µ*t)*_C1, t = infinity)

(45)

 

Subs := diff(S(t), t) = -(beta*lambda+v__1+µ)*S(t)

diff(S(t), t) = -(beta*lambda+v__1+µ)*S(t)

(46)

dsolve({Subs}, S(t))

{S(t) = _C1*exp(-(beta*lambda+v__1+µ)*t)}

(47)
 

``

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