The function

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And to make matters worse, they went on on the next page, and that too does not resolve into anything, even with the book's own input.

Which can be seen here:

 

restart

stelsel := {-x1+7*x2+3*x-x5 = -7, 2*x1+3*x2+4*x3-x5 = 10, 5*x1-3*x2+2*x3-x4-2*x5 = 8}

{-x1+7*x2+3*x-x5 = -7, 2*x1+3*x2+4*x3-x5 = 10, 5*x1-3*x2+2*x3-x4-2*x5 = 8}

(1)

solve(stelsel*{x1, x2, x3, x4, x5})

Error, (in testeq) invalid arguments

 

restart

stelsel := {-x[1]+7*x[2]+x[3]-x[5] = -7, 2*x[1]+3*x[2]+4*x[3]-x[5] = 10, 5*x[1]-3*x[2]+2*x[3]-x[4]-2*x[5] = 8}

{-x[1]+7*x[2]+x[3]-x[5] = -7, 2*x[1]+3*x[2]+4*x[3]-x[5] = 10, 5*x[1]-3*x[2]+2*x[3]-x[4]-2*x[5] = 8}

(2)

solve(stelsel, {x[1], x[2], x[3], x[4], x[5]})

{x[1] = 17/3+(4/3)*x[2]-x[3], x[2] = x[2], x[3] = x[3], x[4] = 53/3-(23/3)*x[2]-7*x[3], x[5] = 4/3+(17/3)*x[2]+2*x[3]}

(3)

variab := [x1, x2, x3, x4, x5]

[x1, x2, x3, x4, x5]

(4)

A, b := GenerateMatrix(stelsel, variab)

Error, mismatched multiple assignment of 2 variables on the left side and 1 value on the right side

 

Totmat := GenerateMatrix(stelsel, variab, augmented = true)

GenerateMatrix({-x[1]+7*x[2]+x[3]-x[5] = -7, 2*x[1]+3*x[2]+4*x[3]-x[5] = 10, 5*x[1]-3*x[2]+2*x[3]-x[4]-2*x[5] = 8}, [x1, x2, x3, x4, x5], augmented = true)

(5)

xopl := LinearSolve(Totmat, free = 'alpha')

LinearSolve(GenerateMatrix({-x[1]+7*x[2]+x[3]-x[5] = -7, 2*x[1]+3*x[2]+4*x[3]-x[5] = 10, 5*x[1]-3*x[2]+2*x[3]-x[4]-2*x[5] = 8}, [x1, x2, x3, x4, x5], augmented = true), free = alpha)

(6)

``

I really dont know what im doing wrong here.

Greetings,

The Function

Download Mapleprimes_Question_Book_2_Paragraph_4.2.2_further_trouble.mw

@Kitonum 

Ahh, i see now, so the solution is on the left, and on the right are the numbers for which that solutions exists. 

Thank you!

Greetings,

The Function

@Kitonum 
Okey, this looks pretty good. Its a lot faster than the manual work. But how would we see if there is 1 solution, no solution, or more than 1 solution? Something is definitely going on @2 and 1. 

Greetings,

The Function 

@Kitonum 

This seems to be the easiest answer, and the one to use for me because there are less mistakes i think i will  make when doing it like you stated. 

Greetings,

The Function

@tomleslie 

Okey, i tried it out. Is a lot of new itterations i have not done yet. Somehow it only works in "text" mode in the worksheet, and not in the "math" mode. I dont know why, but that is the way it is. Maybe its the way it copies and pastes. Im trying to find out what happened, and why.  

What does the " 'nolist' " do?

Greetings,

The Function

@acer 

How confusing! 

Well Ive read back some pages, it turns out that it was displayed somewhere. I feel like scum; how could i have missed this? It was late.. Again.. 

Any way, good to know that "I" can mean more than one thing. 

Greetings,

The Function 

@Carl Love

I did not get the 3x3 Matrix however.

Greetings,

The Function

@Carl Love 

That does explain a lot!

Thank you!

Greetings,

The Function

Just one more question. I really dont know if this is even possible to make it happen. 

It says calculate if possible AB and BA. But i cannot get A in a row into a Matrix. Really dont know how its done. 

So it feel silly to ask, but, is this possible?:

Greetings,

The Function

@Carl Love @Axel Vogt @tomleslie

Thank you guys! This wil save me a lot of time. I really like the answer with the angle brackets, this will work great to get matrixes easily. 

:D

Greetings,

The Function 

@Carl Love 

Well, you are right, its sin, instead of cos. I really have been going over this for hours, thought i had done it right by converting this all to cos. So how is that?! I cant believe ive not seen this through. Things are not changed years ago now are they?! 

Yesterday it was late 3 AM and i had the feeling that i had to do something, so ive been trying and trying to find what it was. And yet i did not see it. The next question i converted yesterday, and double checked. No right answer though. So i will try and find out what is wrong. 

I still dont get how ive read over this. Does this happen to more people? Or is it just me? The thing is with Dutch people nowadays is that; a lot of them when they read they read words that are not there but other words that look like the word, and they read over it (Its the repertoire??). Grades in reading have been going down and down and down for the last 15 years. There is something inherently wrong with Dutch. I could tell you that. When im doing a lot of American English books, there is no such thing as reading things wrong, because it would "kill me" if im thinking things that are not really written down are there instead of the actual words. So if there is no cultural change in how Dutch people read, i suspect the Dutch are doomed. :P 

Me: "so A=B"? (instead of actually being A=A). Some other entity: "Yeah right A=B" (their school of thought: "its him anyways, we dont care if hes wrong, im not wrong. BOOOOHHH"). Me: "allright, if you say so, we are in this together" My (thaught) school of thought ("you are as doomed as i am"). Only for me to find out im hanging on the gallows for longer than a day now. And ohh, are they laughing now. Ha... ha... Its inherently Dutch, and its immoral, and wrong. I dont know how it came to be, but some people made a lot of money, and put a lot of people down. 

Im glad when all the Dutch books are done. Its only a statistics after this book, and that is in Excel.. (I actually like Maple a lot, dont get me wrong). But i am fearing Dutch University, because it will bring more of the established way of being "Dutch" (how could they be so unnationalistic). If only things have gone for the better when i can move to a house closer to the university (the social renting is completely stuck due to mass immigration by refugees), but that may take some time. 

Lets not get anymore offtopic. 

THANK YOU VERY MUCH! 

Greetings,

 

The Function 

@dharr 

But now ive struck some nut i really cannot crack, and there seems to be no real reason why it is so. The thing being my answer is not right while i really did follow the example to the last grief.. If only there was a solution that fits, but there is absolutely nothing i can come up with now. Ive been at it for hours now. 

Thanks!

Greetings,

The Function


 

"f(t):=3*sin(4*t);g(t):=5*cos(4*t-1)"

proc (t) options operator, arrow, function_assign; 3*sin(4*t) end proc

 

proc (t) options operator, arrow, function_assign; 5*cos(4*t-1) end proc

(1)

`αf` := 3*exp(0*I)

3

(2)

`αg` := 5*exp(0-I)

5*exp(-I)

(3)

evalf(%)

2.701511530-4.207354924*I

(4)

`αf`+`αg`

3+5*exp(-I)

(5)

 

 

evalf(%)

5.701511530-4.207354924*I

(6)

abs(`αf`+`αg`)

((3+5*cos(1))^2+25*sin(1)^2)^(1/2)

(7)

sqrt(5.701511530^2+4.207354924^2)

7.085835814

(8)

``

arctan((0-4.207354924)/(5.701511530))

-.6357358242

(9)

7.085835814*exp(0-.6357358242*I)

5.701511530-4.207354924*I

(10)

"sc(t):=7.085835814*(e)^((4*t-0.6357358242)*I)"

proc (t) options operator, arrow, function_assign; 7.085835814*exp(I*(4*t-.6357358242)) end proc

(11)

7.085835814*cos(4*t-.6357358242)

7.085835814*cos(4*t-.6357358242)

(12)

plot([f(t), g(t), f(t)+g(t)], t = 0 .. Pi, y = -10 .. 10)

 

plot(7.085835814*cos(4*t-.6357358242), t = 0 .. Pi, y = -10 .. 10)

 

7.697*cos(4*t-.212)

7.697*cos(4*t-.212)

(13)

plot(7.697*cos(4*t-1.212), t = 0 .. Pi, y = -10 .. 10)

 

NULL

Download Mapleprimes_Question_Book_2_Paragraph_3.9_Question_3_c.mw

@dharr

Thank you for the reply. I came up with the following after realizing that i had gone through this the year before (yes ive not done any homework since the invasion in februari, and ive done digital circuits from the beginning of winter). Any way. This is it:

"fc(t):=(3 sqrt(2))/2-(3 ⅈ sqrt(2))/2"

proc (t) options operator, arrow, function_assign; (3/2)*sqrt(2)-((3/2)*I)*sqrt(2) end proc

(1)

``

``

"gc(t):=2 sqrt(3)+2 ⅈ"

2*sqrt(3)+2*I

(2)

"sc(t):=(3 sqrt(2))/2-(3 ⅈ sqrt(2))/2+2 sqrt(3)+2 ⅈ"

proc (t) options operator, arrow, function_assign; (3/2)*sqrt(2)-((3/2)*I)*sqrt(2)+2*sqrt(3)+2*I end proc

(3)

with(plots)

complexplot([fc(t), 2*sqrt(3)+2*I, sc(t)], x = 0 .. 10, style = point, color = purple)

Warning, expecting only range variable x in expressions [Re(fc(t)), Im(fc(t))] to be plotted but found names [fc, t]

 

 

"color"?""

color

(4)

NULL

`#mover(mi("fc"),mo("&rarr;"))` := arrow(`<,>`(3*sqrt(2)*(1/2), 0-3*sqrt(2)*(1/2)), shape = arrow, color = red); `#mover(mi("gc"),mo("&rarr;"))` := arrow(`<,>`(2*sqrt(3), 2), shape = arrow, color = blue); `#mover(mi("sc"),mo("&rarr;"))` := arrow(`<,>`(3*sqrt(2)*(1/2)+2*sqrt(3), 2-3*sqrt(2)*(1/2)), shape = arrow, color = green)

display(`#mover(mi("fc"),mo("&rarr;"))`, `#mover(mi("gc"),mo("&rarr;"))`, `#mover(mi("sc"),mo("&rarr;"))`, scaling = constrained)

 

``

Greetings,

The Function

Download reply_on_3.9_2b.mw

@acer 
Well, i really cannot see what you did different that what i did, but it gave the right answer. Its exaclty the same syntax, i really dont know what im doing wrong.

Greetings,

The Function

@Carl Love @Kitonum 
Just one question; what is "Opts" in the syntax?

Thank you both for the answers. This is really helpfull.

Its a shame the book does not come up with this sort of solutions for these problems. The Maple solutions usually come at the end of each chapter, and it is not as detailed. I am glad that im getting some great answers on this forum. It really helps a lot to develop my Maple skills which will come in handy for my career, and the engineering im planning to do. 

Greetings,

The Function 

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