## Warning, solutions may have been lost...

hi everyone,
I wanna to solve this equation using maple 12 but I receive this warning message

cos(x)*cosh(x)=1

cos(x)*cosh(x)=-1

tan(x)=tanh(x)

## How to solve Cauchy sequences...

(a) Show that if {an} ∞ n=1 is Cauchy then {a 2 n} ∞ n=1 is also Cauchy. (b) Give an example of a Cauchy sequence {a 2 n} ∞ n=1 such that {an} ∞ n=1 is not Cauchy

## how to solve an exercise with Maple involving the ...

Show that 2^3 + x ^2 − 3x + 2 is O(x ^3 ).

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## How to solve infinite series...

If a dosage Q units of a certain drug is administrated to an individual, then the amount remaining in the bloodstream at the end of t minutes is given by Q*exp^-ct, where c>0. Suppose this same dosage is given at successive T-minute intervals.

a) Show that the amount A(k) of the drug is given by A(k) = ∑n=0k-1 Q*exp(^-ncT).

b) Find an upper bound for the amount of the drug in the bloodsteam after any number of doses.

c) Find the smallest time between doses that will ensure that A(k) does not exceed a certain level M for M>Q.

## Gerschorin's theorem Linear Algebra...

worksheet/expressions/copypasteMaple

Gerschgorin := proc (A::Matrix) local Delta, m, n, AA, R, C, i, c, eig, P, Plt; Delta := proc (i, j) if i = j then 0 else 1 end if end proc; m, n := LinearAlgebra[Dimension](A); AA := Matrix(m, n, proc (i, j) options operator, arrow; Delta(i, j)*abs(A[i, j]) end proc); R := evalm(`&*`(AA, Vector(m, 1))); C := {seq(('plottools[circle]')([Re(A[i, i]), Im(A[i, i])], R[i], color = violet), i = 1 .. m)}; c := {seq(('plottools[point]')([Re(A[i, i]), Im(A[i, i])], color = blue, symbol = diamond), i = 1 .. m)}; eig := evalf(LinearAlgebra[Eigenvalues](A)); P := {seq(('plottools[point]')([Re(eig[i]), Im(eig[i])], color = red, symbol = box), i = 1 .. m)}; Plt := `union`(`union`(C, c), P); plots[display](eval(Plt), scaling = constrained) end proc

A := Matrix([[5, 8, 4, -3], [8, -9, 7, 5], [0, 4, 4, 2], [5, -5, 9, -9]]); evalf(LinearAlgebra[Eigenvalues](A), 3); Gerschgorin(A)

worksheet/expressions/pasteMathML

F := Matrix([[2, -1/2, -1/3, 0], [0, 6, 1, 0], [1/3, -1/3, 5, 1/3], [-1/2, 1/4, -1/4, 4]]); evalf(LinearAlgebra[Eigenvalues](F)); Gerschgorin(F)

Could you print A & F ?

regards

## how to copy and paste from maple 12 a quite big qu...

Hi, as I can't manage to copy and paste on mapleprimes, I would be glad to get a hint ...

## sequence convergence and limit...

Determine wether the sequence below converges or diverges, and if it converges, find the limit.

and,

Thanks

## discontinue in piecewise function...

how can you graph when piecewise function is not continuous?

example:

BB := piecewise (-1.57 < c and c < -1.56, h, -0.06< c and  c < -0.05, aa, -0.5< c and c < 0.04, bb);

## piecewise function...

how to graph in maple

for example

-2 < x < -3, h

-1 < x < -2, b

why do I get the error Error, (in rtable/Sum) invalid arguments

In positive numbers, I get it ok

## something wrong with implicitplot?...

code:

restart;
convert([92*x/790+18*x*(1-y)/1000=0.125,ln(46.59/x)=1/1.5*(ln(0.553/y)+2.5*ln((1-y)/(1-0.553)))],rational);
fsolve(%);
plots:-implicitplot(%%,x=0..2,y=0..1,numpoints=1000,thickness=2,gridlines,color=[blue,red]);

question:

there is something missing with the red line. I can't find the intersect point on the figure.

Is there something wrong with implicitplot?

## Error, (in dsolve/numeric/bvp) initial Newton iter...

Dear All,

I am solving 6 ODE equations with boundary conditions using Runge kutta Felbergh 45 (Maple 12). then, i got this problem.. any suggestion??

Thank you :)

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 Error, (in dsolve/numeric/bvp) initial Newton iteration is not converging
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 Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct
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## how to plot inequality with maple 12...

I'd like to plot the following inequalities:

sqrt(x)<=1/sqrt(2)

1/sqrt(2)<sqrt(x)<=1/sqrt(2)

## Error, (in isolate) cannot isolate for a function ...

Hello,

Im solving 4 ODE equations with BC. im trying to shoot the initial value but im having this error:

""Error, (in isolate) cannot isolate for a function when it appears with different arguments""

anyone could help me???

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 Error, (in isolate) cannot isolate for a function when it appears with different arguments
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## problem in finding particular solution of ode...

hello dear freinds

im new comer in maple.

i want to find  particular solution of an ode by following code:

ode := diff(u[1](t), t, t)+u[1](t) = -(1/4)*a^3*cos(3*beta[0]+3*t)-(3/4)*a^3*cos(beta[0]+t)

m := combine(convert(particularsol(ode), trig))

but maple solution is : m := u[1](t) = (81/32)*a^3*cos(-3*beta[0]+t)-(81/16)*a^3*cos(3*beta[0]+t)-(3/8)*a^3*t*sin(beta[0]+t)+(3/16)*a^3*cos(-beta[0]+t)-(27/16)*a^3*cos(beta[0]+t)+(1/32)*a^3*cos(3*beta[0]+3*t)

but  particular solution is :

u[1](t) = -(3/8)*a^3*t*sin(beta[0]+t)+(1/32)*a^3*cos(3*beta[0]+3*t)

is there any idear for finding the solution?