Write the equation of the line passing through the point A(2, 2, -5), parallel to the plane (P): 2x +3y -z - 17 = 0 and cut the line Delta: x = -2 +3*t, y = 4-t, z = 5 + 2*t.

1) First code.

restart:

with(geom3d):

point(A,2,2,-5):

line(Delta,[-2+3*t,4-t,5+2*t],t):

plane(P,2*x+3*y-z-17=0,[x,y,z]):

parallel(Q,A,P):

Equation(Q):

coordinates(intersection(B,Delta,Q)):

Equation(line(AB,[A,B],t));

Let A(1, 2, 3) be a point; d1: (x-2)/2 = (y+2)/(-1) = (z - 3) / 1

d2: (x--)/(-1) = (y - 1)/2 = (z  + 1) / 1.

Write the equation of the line passing through the point A, perpendicular to d1 and cut d2.

This is my code

restart;with(LinearAlgebra): with(geom3d):

A:=<1,2,3>:

B:=[2*t+2,-t-2,t+3]:

M:=<-m+1, 2*m+1,m-1>:

line(d1,B,t):

a:=convert(ParallelVector(d1),Vector):

v:=M-A:

Is there programs or algorithm to obtain resultant of multivariant polynomials for more than 2 polynomials

Dear Sirs

How to change font there?

==========

Debugger window

restart;
a:='a';
                               a
assume(a>0);
H:=a;
                               a
subs(a=b, H);
       ...

Let M(1; -1; 0) be a point, Delta: (x-2)/2 =(y+1)/(-1) = (z - 1)/1 be a line, (P): x + y + z - 2 = 0 be a plane. Find the coordinates of the point A lies on (P), knowing that the line AM perpendicular to the line Delta and distance from the point A to the line Delta equal to sqrt(33/2).

This is my code

 with(geom3d):

point(M,1,-1,3):

line(Delta,[2*t+2,-t-1,t+1],t):

plane(P,x+y+z+3=0,[x,y,z]):

a:=ParallelVector(Delta):

Is there a bug in the CodeTools:-EncodeName / DecodeName pair?

Consider the following minimal example:

with(CodeTools):
M := module() option package; export f; f := proc() end proc; end module;
EncodeName(M:-f);
DecodeName(%);

The EncodeName gives answer:

_Inert_ASSIGNEDLOCALNAME("f", "PROC", 0, _Inert_ATTRIBUTE(_Inert_NAME("protected", _Inert_ATTRIBUTE(_Inert_NAME("protected")))))

But applying...

how to find concavity of f(t)=(800-t)t/(100+t)

Hi:

Consider this trivial (very contrived) example:

restart:

a:=lambda+3;
b:=Vector([lambda-2, lambda+23]);

subs(lambda=1, a); #works as expected

subs(lambda=1, b); #works as expected

 
assume(lambda, real);  #seems like this causes a problem
subs(lambda=1, a);  #works as expected

subs(lambda=1, b);  #This substitution does NOT work - lambda stays as 'lambda'

I am using maple 15 on...

I converted an ode using the built-in "convert" tool to check some calculations I had done by hand. To my surprise, there was an inconsistency. I converted the ode using PDEtools[dchange], reproducing the steps I had followed manually, and they checked out. So my question is: is there a sign error in convert? (and therefore a bug) or are both conversions correct, and if so are there any lessons to be learned? (is it related to the equation's symmetries?)

Thanks for your comments.

isnin:=proc(A)
local i,j,f,B:
B[1] := 0:
for i from 1 to numccs do

f:=Size([entries(B)][i][1],2); <---

for j from 1 to f do
if Equal([entries(A)][1][1],[entries(B)][i][1][j]) then
return false:
end if:
end do:
end do:
return true:
end proc:
 

Do you know why maple wont evaluate f?

If it's not something obvious context is below...

If there's some equivalent to a dynamic array in maple I'd really like to know!

I am currently taking a course in quantum mechanics using the second edition of McQuarrie's Quantum Chemistry text. I plan to take a QM II course, more concentrating on atomic and molecular spectra. I have been using Mathcad 15, which includes Maple functionality (please pardon my stating the obvious). Mathcad, however, seems to lack functionality (or I have not found it) that would be helpful, like the ability to easily define an operator. Since...

Find the polynomial y=f(x) such that f(-6)=2400,f(-4)=432,f(-3)=120,f(-2)=16,f(-1)=0,f(0)=0,f(1)=-8,f(2)=0