## 0 Reputation

10 years, 138 days

## @pagan  I follow you now, makes se...

I follow you now, makes sense.

Does it matter how many digits I print newsteadmod to? currently i have set 15.

Thanks :)

## @pagan  I follow you now, makes se...

I follow you now, makes sense.

Does it matter how many digits I print newsteadmod to? currently i have set 15.

Thanks :)

## @pagan  I dont quite follow you, b...

I dont quite follow you, being a new user to maple. Do you mind editing my code and showing me. I find I learn stuff better when I see the code, makes me understand it where I went wrong.

## @pagan  I dont quite follow you, b...

I dont quite follow you, being a new user to maple. Do you mind editing my code and showing me. I find I learn stuff better when I see the code, makes me understand it where I went wrong.

## Ok here is the program now:eq := 0...

Ok here is the program now:

eq := 0.178e-1*x*tan(0.2e-4*sqrt(x))^2 = 0.232e13-x;

neweq := subs(x = 10^y, eq);

Digits := 15;

newans := Student:-Calculus1:-Roots(neweq, y = log[10](10^10) .. log[10](10^11));

newans2 := Student:-Calculus1:-Roots(simplify((rhs-lhs)(neweq)), y = log[10](10^10) .. log[10](10^11));

all := [op(evalf[14]({op(newans), op(newans2)}))];

Digits := 100;

allmod := map(proc (t) options operator, arrow; 10^t end proc, all);

Digits := 15; newestmod := evalf(allmod);

Digits := 100;

check := map(proc (t) options operator, arrow; eval((rhs-lhs)(eq), x = t) end proc, allmod);

Digits := 15; evalf(check);

Here is the output

`                                             [10.7405813131081, 10.7482811219187]              [10.7405813131081, 10.7482811219186]               [10.740581313108, 10.748281121919]                                    [5.50276939410435 x10^10  , 5.60120053883583x10^ 10  ]           {the solutions)`
`              [167.706091024260, 403.172634297628]    `
` {the solutions plugged back in the equation to give these last two values, `
`these should be zero}`
` `
`As you can see I still have a problem, the so called solutions that are outputted dont seem to `
`check out when plugged back in.`

## Ok here is the program now:eq := 0...

Ok here is the program now:

eq := 0.178e-1*x*tan(0.2e-4*sqrt(x))^2 = 0.232e13-x;

neweq := subs(x = 10^y, eq);

Digits := 15;

newans := Student:-Calculus1:-Roots(neweq, y = log[10](10^10) .. log[10](10^11));

newans2 := Student:-Calculus1:-Roots(simplify((rhs-lhs)(neweq)), y = log[10](10^10) .. log[10](10^11));

all := [op(evalf[14]({op(newans), op(newans2)}))];

Digits := 100;

allmod := map(proc (t) options operator, arrow; 10^t end proc, all);

Digits := 15; newestmod := evalf(allmod);

Digits := 100;

check := map(proc (t) options operator, arrow; eval((rhs-lhs)(eq), x = t) end proc, allmod);

Digits := 15; evalf(check);

Here is the output

`                                             [10.7405813131081, 10.7482811219187]              [10.7405813131081, 10.7482811219186]               [10.740581313108, 10.748281121919]                                    [5.50276939410435 x10^10  , 5.60120053883583x10^ 10  ]           {the solutions)`
`              [167.706091024260, 403.172634297628]    `
` {the solutions plugged back in the equation to give these last two values, `
`these should be zero}`
` `
`As you can see I still have a problem, the so called solutions that are outputted dont seem to `
`check out when plugged back in.`

## Yes that's what I meant.....

The program is now

eq := 0.178e-1*x*tan(0.2e-4*sqrt(x))^2 = 0.232e13-x;

neweq := subs(x = 10^y, eq);

Digits := 15;

newans := Student:-Calculus1:-Roots(neweq, y = log[10](10^10) .. log[10](2*10^12));

newans2 := Student:-Calculus1:-Roots(simplify((rhs-lhs)(neweq)), y = log[10](10^10) .. log[10](2*10^12));

all := [op(evalf[14]({op(newans), op(newans2)}))];

Digits := 100;

allmod := map(proc (t) options operator, arrow; 10^t end proc, all);

Digits := 15; newestmod := evalf(allmod);

Digits := 100;

check := map(proc (t) options operator, arrow; eval((rhs-lhs)(eq), x = t) end proc, allmod);

Digits := 15;

evalf(check)

the program should output the solutions and then check them by plugging them into the equation, to see if the equation is satisfied.

A whole lot of values are outputted but the solution (that I know) are not.

## Yes that's what I meant.....

The program is now

eq := 0.178e-1*x*tan(0.2e-4*sqrt(x))^2 = 0.232e13-x;

neweq := subs(x = 10^y, eq);

Digits := 15;

newans := Student:-Calculus1:-Roots(neweq, y = log[10](10^10) .. log[10](2*10^12));

newans2 := Student:-Calculus1:-Roots(simplify((rhs-lhs)(neweq)), y = log[10](10^10) .. log[10](2*10^12));

all := [op(evalf[14]({op(newans), op(newans2)}))];

Digits := 100;

allmod := map(proc (t) options operator, arrow; 10^t end proc, all);

Digits := 15; newestmod := evalf(allmod);

Digits := 100;

check := map(proc (t) options operator, arrow; eval((rhs-lhs)(eq), x = t) end proc, allmod);

Digits := 15;

evalf(check)

the program should output the solutions and then check them by plugging them into the equation, to see if the equation is satisfied.

A whole lot of values are outputted but the solution (that I know) are not.

## Yes thats correct. Thanks so much pagan...

Yes thats correct.

Thanks so much pagan. I wish i was taught maple at university, it wasn't part of my course. Maple is a very useful program.

## Yes thats correct. Thanks so much pagan...

Yes thats correct.

Thanks so much pagan. I wish i was taught maple at university, it wasn't part of my course. Maple is a very useful program.

## pagan your method is excellent!&nb...

it agrees with almost all my answers when I use another method (much longer that requires plotting and searching for roots)

However i noticed that when you change your equation (only changed the underlined values)

```restart:
eq:=tan(4*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
/tan(4*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
= -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12
/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2:```
`to the quation`
```restart:
eq:=tan(6*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
/tan(6*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
= -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12
/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2:```
` `
`I get values from your method:`
`[8.23681389099981*10^5, 1.63071661915857*10^6, 1.83601970432122*10^6]`
`when my values (from my method) are:`
 1.836019704*10^6 1.129804944*10^6 8.236813891*10^5
`one value of yours is incorrect here`

## pagan your method is excellent!&nb...

it agrees with almost all my answers when I use another method (much longer that requires plotting and searching for roots)

However i noticed that when you change your equation (only changed the underlined values)

```restart:
eq:=tan(4*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
/tan(4*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
= -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12
/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2:```
`to the quation`
```restart:
eq:=tan(6*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
/tan(6*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))
= -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12
/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2:```
` `
`I get values from your method:`
`[8.23681389099981*10^5, 1.63071661915857*10^6, 1.83601970432122*10^6]`
`when my values (from my method) are:`
 1.836019704*10^6 1.129804944*10^6 8.236813891*10^5
`one value of yours is incorrect here`

## ok so the task doesnt work for irrationa...

ok so the task doesnt work for irrationals?, thats a shame because solutions are always irrational to that equation.

I have also tried

tan(2*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))/tan(2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2)) = -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2;

lhs(%)-rhs(%);

EQ := subs(x^2 = z, %);

RootOf(%, z);

z0 := allvalues(%);

sqrt(%);

evalf(%)

Each time i change the bolded 2 in the top equation to another value, say 3, i get the same answer. So is it because it only works for rationals and not irrationals?

Thankyou very much for the help.

## ok so the task doesnt work for irrationa...

ok so the task doesnt work for irrationals?, thats a shame because solutions are always irrational to that equation.

I have also tried

tan(2*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))/tan(2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2)) = -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2;

lhs(%)-rhs(%);

EQ := subs(x^2 = z, %);

RootOf(%, z);

z0 := allvalues(%);

sqrt(%);

evalf(%)

Each time i change the bolded 2 in the top equation to another value, say 3, i get the same answer. So is it because it only works for rationals and not irrationals?

Thankyou very much for the help.

## I tried this: tan(2*(1.1575*10^12/(...

I tried this:

tan(2*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2))/tan(2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*10^(-6)*(1/2)) = -4*x^2*(5.555*10^11/(1-.5)^1.2-x^2)^(1/2)*(1.1575*10^12/(1-.5)^1.2-x^2)^(1/2)/(1.1575*10^12/(1-.5)^1.2-2*x^2)^2;

lhs(%)-rhs(%);

RootOf(%, x);

z0 := allvalues(%);

evalf(%);

i get 6 solutions but they seem incorrect:

-1.127205209*10^6, -1.129691937*10^6, -9.942135523*10^5, -1.630716619*10^6, -1.630716619*10^6, 1.129691937*10^6

one of the solutions should be 1.131417176*10^6 (i know this is definately a solution)

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