Kitonum

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14 years, 256 days

MaplePrimes Activity


These are answers submitted by Kitonum


 

 

restart;
lambda1:=-sqrt(64-mu^2):
lambda2:=sqrt(64-mu^2):
plot3d([[lambda1-lambda1*t,mu*t,3-6*t],[lambda2-lambda2*t,mu*t,3-6*t]], t=-8..8, mu=-8..8, grid=[100,100]);
P1:=plots:-implicitplot3d(9*x^2*(3-z)^2+9*y(3+z)^4 = 16*(-z^2+9)^2, x=-8..8, y=-3..3, z=-3..3, style=surface, grid=[50,50,50]):
P2:=plots:-spacecurve([[t,0,3], [0,t,-3]], t=-8..8, color=red, thickness=3):
plots:-display(P1, P2);

 

 

 

Equation of Generatrix :"`G__lambda,mu`≡{[[x=lambda-lambdat],[y=mu t],[z=3-6 t]](t in `ℝ`)" with lambda^2+mu^2 = 64

Cartesian equation of surface:  "S&equiv;{[[9 x^(2)*(3-z)^(2)+9 y^(2)(3+z)^(2)=16*(9-z^(2))^(2) if z<>3 and z<>-3],[[-8<=x<=8 and y=0] if z=3],[[ x=0 and -8<=y<=8] if z=-3]]"


 

Download SurfaceMP_new.mw
 

 


 

restart;
with(combinat):

permute([a,b],1);

[[a], [b]]

(1)

permute([p$3,q$3], 3);

[[p, p, p], [p, p, q], [p, q, p], [p, q, q], [q, p, p], [q, p, q], [q, q, p], [q, q, q]]

(2)

permute([5$3,7$3], 3);

[[5, 5, 5], [5, 5, 7], [5, 7, 5], [5, 7, 7], [7, 5, 5], [7, 5, 7], [7, 7, 5], [7, 7, 7]]

(3)

permute([5$3,7$3,9$3], 2);

[[5, 5], [5, 7], [5, 9], [7, 5], [7, 7], [7, 9], [9, 5], [9, 7], [9, 9]]

(4)

permute([5$3,7$3,9$3], 4);

[[5, 5, 5, 7], [5, 5, 5, 9], [5, 5, 7, 5], [5, 5, 7, 7], [5, 5, 7, 9], [5, 5, 9, 5], [5, 5, 9, 7], [5, 5, 9, 9], [5, 7, 5, 5], [5, 7, 5, 7], [5, 7, 5, 9], [5, 7, 7, 5], [5, 7, 7, 7], [5, 7, 7, 9], [5, 7, 9, 5], [5, 7, 9, 7], [5, 7, 9, 9], [5, 9, 5, 5], [5, 9, 5, 7], [5, 9, 5, 9], [5, 9, 7, 5], [5, 9, 7, 7], [5, 9, 7, 9], [5, 9, 9, 5], [5, 9, 9, 7], [5, 9, 9, 9], [7, 5, 5, 5], [7, 5, 5, 7], [7, 5, 5, 9], [7, 5, 7, 5], [7, 5, 7, 7], [7, 5, 7, 9], [7, 5, 9, 5], [7, 5, 9, 7], [7, 5, 9, 9], [7, 7, 5, 5], [7, 7, 5, 7], [7, 7, 5, 9], [7, 7, 7, 5], [7, 7, 7, 9], [7, 7, 9, 5], [7, 7, 9, 7], [7, 7, 9, 9], [7, 9, 5, 5], [7, 9, 5, 7], [7, 9, 5, 9], [7, 9, 7, 5], [7, 9, 7, 7], [7, 9, 7, 9], [7, 9, 9, 5], [7, 9, 9, 7], [7, 9, 9, 9], [9, 5, 5, 5], [9, 5, 5, 7], [9, 5, 5, 9], [9, 5, 7, 5], [9, 5, 7, 7], [9, 5, 7, 9], [9, 5, 9, 5], [9, 5, 9, 7], [9, 5, 9, 9], [9, 7, 5, 5], [9, 7, 5, 7], [9, 7, 5, 9], [9, 7, 7, 5], [9, 7, 7, 7], [9, 7, 7, 9], [9, 7, 9, 5], [9, 7, 9, 7], [9, 7, 9, 9], [9, 9, 5, 5], [9, 9, 5, 7], [9, 9, 5, 9], [9, 9, 7, 5], [9, 9, 7, 7], [9, 9, 7, 9], [9, 9, 9, 5], [9, 9, 9, 7]]

(5)

 


 

Download permutations.mw

restart;
with(algcurves):

f:=2*z^6 + z^7/2 - (5*z^11)/4 + 4*z^22 + (29*z^34)/10 - z^40 - (13*z^43)/2 + w^38*(z^2 - z^7/4) + 
 w^49*(-z^9 + z^13/4 + 2*z^14) + w^34*((7*z^14)/3 - (3*z^18)/2) + w^47*(z^10/3 + (7*z^11)/4 + (8*z^21)/5) + 
 w^24*(4*z^8 + (4*z^25)/5 - (3*z^27)/2) + w^9*((-6*z^2)/5 - z^6/2 + (7*z^31)/3) + 
 w^16*((7*z^21)/3 + (4*z^27)/5 + (4*z^32)/3) + w^18*(-6*z^14 - 2*z^31 - z^33) + w^3*(2*z^17 + (7*z^34)/2) + 
 w^16*((-3*z^5)/4 - 2*z^36 + z^39/3) + w^50*(-1/3*z^23 - (7*z^40)/2 + z^42) + w^4*((-3*z^30)/2 + (4*z^38)/3 + (8*z^42)/5) + 
 w^33*(-3*z^4 + (8*z^22)/3 - (8*z^43)/5) + w^16*(-1/4*z^26 - (3*z^41)/4 - z^43) + w^48*((2*z^2)/3 + 6*z^26 + (3*z^43)/5) + 
 w^49*(2*z^18 + z^36 - 2*z^44) + w^10*((-2*z^11)/5 - (3*z^26)/2 + z^45) + w^40*(-1/2*z^20 - z^29 + z^46) + 
 w^36*(-4 + 8*z^13 - (7*z^47)/4) + w^14*((7*z^24)/5 - 6*z^32 - 6*z^49) + w^22*(-2*z^27 - (8*z^50)/3) + 
 w^2*((3*z^10)/5 + (7*z^24)/4 - z^50/4);

genus(f,z,w);

                                                         2268

restart;
L:=[k$1,y$23,f$25];
L0:=sort(ListTools:-Collect(L), key=(t->t[2]));
map(t->t[1], L0); 
map(t->t[2], L0);

    

 

Yes, this is indeed an ellipse, most of which is below the Ox axis and it is strongly elongated along this axis. To see it, you need to lengthen the axes and use the scaling=constrained option to correctly show its shape:

plots:-implicitplot(1/1350000000000000000*x^2-1/14580000000000000000000000000000000*x*y+1/5400000000000000*y^2-1/2250000000*x+173/5400000000*y-1=0, x=-10^10..10^11, y=-3*10^8..3*10^7, gridrefine=3, scaling=constrained, size=[1000,100]);

                               

Use the inert multiplication sign  %.  and  InertForm:-Display( ... , inert=false)  command so that the multiplication sign is not gray, but the usual blue color:

restart;
U := <u1, u2>;
K := Matrix(2, 2, symbol = k);
K%.U;
InertForm:-Display(%, inert=false);

                                   

The task is easily solved in Maple without any financial packages. In the code below, q means how many times the debt increases monthly, x means the monthly payment, and  p[n]  means debt at the end of the n-th month:

restart;
q:=1+9/12/100:
p[1]:=120000*q-x:
for n from 2 to 30*12 do
p[n]:=p[n-1]*q-x;
od:
fsolve(p[30*12]=0);

                                                           965.5471403

We can find all the solutions of this system with rational coefficients, depending on 6 parameters:

restart;
eqs:=eval~(k[1]*x^3+k[2]*x^2*y+k[5]*x^2*z+k[3]*x*y^2+k[6]*x*y*z+k[8]*x*z^2+k[4]*y^3+k[7]*y^2*z+k[9]*y*z^2+k[10]*z^3,{{x=1,y=1,z=1},{x=RootOf(_Z^3-4*_Z^2+_Z+1,index=1),y=RootOf(_Z^3-4*_Z^2+_Z+1,index=2),z=RootOf(_Z^3-4*_Z^2+_Z+1,index=3)},{x=RootOf(_Z^3-4*_Z^2+_Z+1,index=2),y=RootOf(_Z^3-4*_Z^2+_Z+1,index=3),z=RootOf(_Z^3-4*_Z^2+_Z+1,index=1)},{x=RootOf(_Z^3-4*_Z^2+_Z+1,index=3),y=RootOf(_Z^3-4*_Z^2+_Z+1,index=1),z=RootOf(_Z^3-4*_Z^2+_Z+1,index=2)}}):
sol:=solve(eqs):
evalf[20](sol):
Sol:=identify(evalf[15](%));

       


Edit. To obtain integer solutions, you can do

isolve(Sol);

         

 

This can be done using one command  expand:

x^(n-1)*(expand((n*x^n - 2*n*x^(n - 1) + x^n)/x^(n-1)));

                                           

This can be done in many ways. Here is one:

restart;
L:=[["O",3.85090000,0.45160000,0.00120000],
["O",-2.59990000,1.40410000,-0.00180000],
["N",-1.57050000,-0.71710000,0.00010000],
["C",-0.20660000,-0.42310000,-0.00020000],
["C",0.22050000,0.90470000,0.00040000],
["C",0.72980000,-1.45700000,-0.00070000],
["C",1.58410000,1.19860000,0.00020000],
["C",2.09330000,-1.16290000,-0.00070000],
["C",2.52040000,0.16480000,-0.00030000],
["C",-2.64850000,0.17820000,0.00090000],
["C",-3.97350000,-0.54200000,0.00100000],
["H",-0.44360000,1.75770000,0.00120000],
["H",0.41130000,-2.49630000,-0.00100000],
["H",-1.80100000,-1.70860000,0.00010000],
["H",1.90530000,2.23700000,0.00090000],
["H",2.81800000,-1.97260000,-0.00080000],
["H",-4.06550000,-1.14630000,-0.90580000],
["H",-4.79040000,0.18440000,0.02880000],
["H",-4.04450000,-1.18860000,0.88020000],
["H",3.96500000,1.41760000,0.00170000]]:

k:=0: n:=nops(L):
for i from 1 to n do
if L[i,1]="H" then k:=k+1; S[i]:=i fi;
od:
S:=convert(S, list);

                                            S := [12, 13, 14, 15, 16, 17, 18, 19, 20]

expr := ``(a*f(x) + b*f(x) + a*g(x)) + 1/(a*f(x) + b*f(x) + a*g(x));
applyop(expand,1,simplify(expr));

 

restart;
T:=table([1 = NULL, 2 = NULL, 3 = NULL, 4 = NULL, 5 = NULL, 6 = NULL, 7 = 5, 9 = NULL, 8 = NULL, 11 = 4, 10 = NULL, 13 = NULL, 12 = NULL, 15 = 9, 14 = NULL, 18 = NULL, 19 = 8, 16 = 9, 17 = NULL, 22 = 9, 23 = NULL, 20 = NULL, 21 = 8, 27 = NULL, 26 = 8, 25 = 4, 24 = NULL, 31 = NULL, 30 = 9, 29 = NULL, 28 = 9, 36 = NULL, 37 = 9, 38 = 9, 39 = NULL, 32 = 5, 33 = NULL, 34 = NULL, 35 = NULL, 45 = NULL, 44 = NULL, 47 = NULL, 46 = NULL, 41 = 8, 40 = NULL, 43 = NULL, 42 = NULL, 54 = NULL, 55 = NULL, 52 = NULL, 53 = NULL, 50 = NULL, 51 = NULL, 48 = 5, 49 = 9, 60 = 8, 59 = NULL, 58 = 7, 57 = 7, 56 = NULL]):
T1:=table(select(t->rhs(t)<>NULL, op(op(T))));
op~([indices(T1)]);
restart;
irem(expand((2 + sqrt(3))^15 + (2 - sqrt(3))^15), 2017);

                                                    685


This number  (2 + sqrt(3))^15 + (2 - sqrt(3))^15  is actually an integer. If you expand the brackets (raise to the 15th power), then all the square roots will disappear.

restart;
V1:=Vector[row]([a*z+b*(x+I*y), -b*z+a*(x+I*y)]);
V2:=Vector([a*z+b*(x-I*y), -b*z+a*(x-I*y)]);
factor(evalc(V1.V2));
simplify(%, {a^2+b^2=1});

The  evalc  command allows you to operate on complex numbers, assuming all parameters (a, b, x, y, z) are real numbers. The signs of these parameters do not matter for this example.

You missed 2 parentheses  draw( [ ... ] )

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