@rlopez 
Hello there,
Appreciate your response, but I just have one question.
How do you insert V in the following?
q:=solve(abs(sin(x)-x)=4\/1000,x):
evalf(q[1]);
evalf(q[2])

I forgot to link this one, but it is more relevant than the previous. I need to let f(x) = sin(x), and test this relation - the difference here, being that we now have numbers to apply to our relation:

Text:
Show that |f(x) - P₁(x)| < 0.004, when x is -0.1 < x < 0.1

when
P₁(x) is the first taylor series (polynomial)

@mmcdara Appreciate the answer :)

If I don't bother you, how would the requirement be set, if I wanna do something else?
Like if I wanna find maxima and minima for example.
Just wanna get the hang of how you contruct the formula, so I can do it in the future w/o asking

@mmcdara 
These two functions are in question
f(x) = 2.0*cos(1.5*x + 4.0) + 2.2
g(x) = 2.0*cos(1.6*x + 3.85) + 2.0

To be more specific, I wanna set a criteria, so that Maple only calculates these first crossing points, instead of every single one:
https://media.discordapp.net/attachments/906568912366338069/906584510760628254/unknown.png

Hope this makes a bit more sense :)