## 160 Reputation

8 years, 296 days

## MaplePrimes Activity

### These are replies submitted by max125

I downloaded the patch maple 2016.2 and as you can see Tautology command is still not working.

@nm Thanks for the prompt reply. Is there a place in maple where you lodge bug reports for the developers, maybe for the next version of it.

This seems to only affect the letter p.  I just checked by manually entering all the letters. Substituting p1 for p for example seems to be a simple enough workaround when doing logic.

## spam?...

"So instead, you'll be much better off in need of an anti-wrinkle skin care system close to Internet.  ...."

Is this spam? Math geeks don't care much for skin care products. Ply your wares elsewhere.

## surd and real numbers...

I just found out about root[] by googling a few minutes ago. Isn't the surd supposed to be used for real numbers? That's why I used it, I wanted to stay to real numbers.

For example  surd(-8,3) gives me 2 , but (-8)^(1/3) does not return 2 because Maple treats it as a complex number.

## the problem came up...

The problem came up when I was asked to compose two functions and determine if the composed function is one to one, onto, or neither.

Full link to the question :

http://s3.amazonaws.com/chegg.media.images/board/904/904d6355-379d-4de3-91e1-0dc8926f99f3-original.png

I defined h(x) = x^4, g(x) = surd(x,8).

I wanted to show that the composition f=h(g(x)) is not onto by showing there is no solution

to h(g(x) = -2.

The root[] command might be better for solving equations than the surd.

Here is a screenshot, with both surd and rational exponents for comparison.

The root[8](x) command gives me the expected response of no solution.

Should I just stick with rational exponents?

It would be nice if Maple would say 'no solution' when there is no result.

Otherwise someone might think their version of Maple is buggy or something.

Also I notice Maple does not simplify exponents by default. For example (x^4)^(1/8) does not become x^(1/2).

One way seems to be to make an assumption.

## @broe I would define new trig funct...

I would define new trig functions by appending the letter d to the default trig functions, which accept degrees as arguments for sin,cos, tan,etc. and output degrees for the inverse trig functions.

sind:=d->sin(Pi/180*d):
cosd:=d->cos(Pi/180*d):
tand:=d->tan(Pi/180*d):
cscd:=d->csc(Pi/180*d):
secd:=d->sec(Pi/180*d):
cotd:=d->cot(Pi/180*d):
arcsind:=y->180/Pi*(arcsin(y)):
arccosd:=x->180/Pi*(arccos(x)):
arctand:=m->180/Pi*(arctan(m)):
arccotd:=a->180/Pi*(arccot(a)):
arcsecd:=b->180/Pi*(arcsec(b)):
arccscd:=c->180/Pi*(arccsc(c)):

To see the result,  https://i.imgur.com/cpxzzMK.png

## Oh I feel so ......

Thanks guys. I didnt realize I forgot the colon when I defined L.

And yes, I meant it to be an ordered list, check f(1) = h(1), then f(2) = h(2), etc.

Let me use different numbers to clear up ambiguity.

I have two sets

f:={8,9,6,7}; h:={8,9,7,6} ; L=seq(i,i=1..4):

for i in L do
if f[i]=h[i] then
print(f[i]);
end if;
end do;

The output should be {8,9}.

So it doesn't make a difference if you use {}  or [ ], when we define f,h.

Can anyone recommend me a maple programming guide, for newbies?

@Preben Alsholm Thanks for the reply. I will have to do some research to understand these terms. Do you have a suggestion for learning Maple more in depth

## looks like a good book...

I might want to buy this.

## what is going on here...

@Preben Alsholm what is going on internally here. nothing seems to happen here

According to this, it uses a remember table

https://en.wikibooks.org/wiki/Maple/Getting_Started#Defining_a_function_with_Maple

> f(x):=2*x+2;


defines f as a procedure with a "remember table" that is assigned only for the argument x:

> f(u);

$\mathrm{f}(u)\,$

and

> f(x)=2*x+2;



is an equation.

## interesting...

@Preben Alsholm And based on your example, we could say, evaluating functions comes before exponentiating (order of operations).

That is, x^2(3) = x^(2(3)) = x^(2) = x^2

So to answer the question above

> f:=x^2
> f(3)
why is output: x(3)^2

It is treating 'x' as a function, which we could have defined earlier.

In other words, f(3) = (x(3))^2 = x(3)^2

The only way to escape this is to insert a multiplication sign.

It is interesting that 2(3) evaluates to 2 treating it as a constant function. A proviso, this must be in maple input. In 2d math mode, 2(3) is assumed to be multiplication and evaluates to 6.

## I see the product line. thanks...

@Markiyan Hirnyk woops, i see now. thanks :)

## @Markiyan Hirnyk Sorry I don't understan...

@Markiyan Hirnyk I don't understand.

## Interested...

I an interested to see how Maple can help students learn new concepts.

In my experiencing using Maple lets you avoid tedious calculation so you have a clear idea of the target solution. It can also aid in the understanding of the manual calculations.

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