## 300 Reputation

12 years, 222 days

## Where is wrong in this code?...

Maple

This is my code

restart; L := [];
for a from -10 to 10 do
for b from -10 to 10 do
for c from -10 to 10 do
k := (-a*b*c+a*b*z+a*c*y+b*c*x)/igcd(a*b, b*c, c*a, a*b*c); if a*b*c <> 0 then L := [op(L), [[a, 0, 0], [0, b, 0], [0, 0, c]], k*signum(lcoeff(k)) = 0] end if end do end do end do; nops(L); L

I think my code was error, because  a from -10 to 10.

## How do I write the equation of the plane...

Maple

I have a code to write the equation of the plane passing through three points

restart:
with(geom3d):
point(A,1,-1,3):
point(B,-15,-17,11):
point(C,2,1,0):
plane(P,[A,B,C],[x,y,z]):
n:=NormalVector(P):
cdn:=ilcm(op(denom~(n))):
n:=cdn*n:
k:=igcd(n[1],n[2],n[3]):
if n[1]<>0 then sign(n[1])*cdn/k*sort(Equation(P))
elif n[2] <> 0 then sign(n[2])*cdn/k*sort(Equation(P))
else sign(n[3])*cdn/k*sort(Equation(P))
end;

How do I write the equation of the plane passing through list of following three points?
L := [[[-12, 2, -1], [-11, 1, -5], [-10, -2, 3]], [[-12, 2, -1], [-11, 1, -5], [-10, 6, 3]], [[-12, 2, -1], [-11, 1, -5], [-9, 5, -7]], [[-12, 2, -1], [-11, 1, -5], [-9, 8, -4]], [[-12, 2, -1], [-11, 1, -5], [-7, -6, -2]], [[-12, 2, -1], [-11, 1, -5], [-7, -2, -8]], [[-12, 2, -1], [-11, 1, -5], [-7, -2, 6]], [[-12, 2, -1], [-11, 1, -5], [-7, 3, -9]], [[-12, 2, -1], [-11, 1, -5], [-7, 3, 7]], [[-12, 2, -1], [-11, 1, -5], [-7, 6, -8]], [[-12, 2, -1], [-11, 1, -5], [-7, 9, 3]], [[-12, 2, -1], [-11, 1, -5], [-7, 10, -2]], [[-12, 2, -1], [-11, 1, -5], [-6, -4, -7]], [[-12, 2, -1], [-11, 1, -5], [-6, -4, 5]], [[-12, 2, -1], [-11, 1, -5], [-6, 8, -7]], [[-12, 2, -1], [-11, 1, -5], [-6, 8, 5]], [[-12, 2, -1], [-11, 1, -5], [-4, -6, 3]], [[-12, 2, -1], [-11, 1, -5], [-4, -2, -9]], [[-12, 2, -1], [-11, 1, -5], [-4, -2, 7]], [[-12, 2, -1], [-11, 1, -5], [-4, 6, -9]], [[-12, 2, -1], [-11, 1, -5], [-4, 6, 7]], [[-12, 2, -1], [-11, 1, -5], [-4, 10, 3]], [[-12, 2, -1], [-11, 1, -5], [-2, -6, 3]], [[-12, 2, -1], [-11, 1, -5], [-2, 6, -9]], [[-12, 2, -1], [-11, 1, -5], [-2, 6, 7]], [[-12, 2, -1], [-11, 1, -5], [-2, 10, 3]], [[-12, 2, -1], [-11, 1, -5], [3, 5, -7]], [[-12, 2, -1], [-11, 1, -5], [3, 8, -4]], [[-12, 2, -1], [-11, 1, -5], [4, -2, 3]], [[-12, 2, -1], [-11, 1, -5], [4, 6, 3]], [[-12, 2, -1], [-11, 1, -5], [5, 6, -2]], [[-12, 2, -1], [-11, 1, 3], [-10, -2, -5]], [[-12, 2, -1], [-11, 1, 3], [-10, 6, -5]], [[-12, 2, -1], [-11, 1, 3], [-9, 5, -7]], [[-12, 2, -1], [-11, 1, 3], [-9, 8, -4]], [[-12, 2, -1], [-11, 1, 3], [-7, -6, -2]], [[-12, 2, -1], [-11, 1, 3], [-7, -2, -8]], [[-12, 2, -1], [-11, 1, 3], [-7, -2, 6]], [[-12, 2, -1], [-11, 1, 3], [-7, 6, -8]], [[-12, 2, -1], [-11, 1, 3], [-7, 9, -5]]]

## How do I find a logarith in term a given...

Maple

Knowing that log[12](27) = a. How can I find log[36](24) in term a in Maple?

## Solve equation with integer solutions...

Maple

At here http://www.mapleprimes.com/questions/146604-How-To-Choose-The-Parameters-To-The, I posted my question and I got the answer. Now I have a new question, is there a program that can be solved for many equation with integers solutions. For example, the equation has the form sqrt(a x + b) = c x + d, sqrt(a x + b) - sqrt(c x + d) = k,...

With Mathematica, my code that solve the equation a x + b == Sqrt[c x + d]

ClearAll[a, b, c, d];
sol = x /. Solve[{a x + b == Sqrt[c x + d]} , x, Reals];
ClearAll[f];
(f[{a_, b_, c_, d_}] :=
Quiet@Check[And @@ (IntegerQ /@ #), False]) &[sol]
poss = Select[
Tuples[Range[1,
20], {4}], #[[1]] =!= 0 && #[[2]]^2 - #[[4]] =!= 0 &&
GCD[#[[1]], #[[3]], #[[2]], #[[4]]] == 1 && f[#] &];
Take[poss, Length[poss]];
With[{s = sol},
getSolution[poss_] := Block[{a, b, c, d}, {a, b, c, d} = poss;
Join[poss, s]]]
getSolution /@ poss

When I repair  a x + b == Sqrt[c x + d] into Sqrt[a x + b] + Sqrt[c x + d] == k, then I have a new propram, or if I replace into Sqrt[a x + b] - Sqrt[c x + d] == k, I  have also a new program. How can I do like that with Maple?

## Problem with RealDomain:-solve...

Maple

I want to solve the equation

sqrt(x)+sqrt(-x^2+1) = sqrt(-4*x^2-3*x+2)

in Real domain. I tried

RealDomain:-solve(sqrt(x)+sqrt(-x^2+1) = sqrt(-4*x^2-3*x+2), x);

and I got -5/9+(1/9)*sqrt(34).

But, with Mathematica, I posted my question at http://mathematica.stackexchange.com/questions/51316/how-can-i-get-the-exact-real-solution-of-this-equation

``x ==-1-Sqrt[2]|| x ==1/9(-5+Sqrt[34])``
``x ==-1-Sqrt[2] ``