Help with inverse trig functions

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
3 replies · 2K views
vysero
Messages
134
Reaction score
0
Here is my problem:

cot(arcsin(x))

my awnser:

cot= x/(1-x)^1/2

The online program were suppose to use says I am wrong but I am not sure what I did wrong.
 
on Phys.org
vysero said:
Here is my problem:

cot(arcsin(x))

my answer:

cot= x/(1-x)^1/2

The online program were suppose to use says I am wrong but I am not sure what I did wrong.
What's the question that you're trying to answer?

The answer you give makes no sense whatsoever.
 
Draw a right triangle, with θ being the acute angle in the triangle. Let θ = arcsin(x), and label the sides and hypotenuse according to this definition.

The problem boils down to evaluating cot(θ).

Your answer SHOULD NOT start with "cot =" since cot by itself is meaningless in this context. If you are doing your work on paper, your work should start with cot(arcsin(x)) = ... and end up with what you found, which is actually not too far off.
 
The simplest way to do this is to imagine a right triangle with one angle [itex]\theta[/itex], "opposite side" to [itex]\theta[/itex] of length x, and hypotenuse of length 1 so that [itex]sin(\theta)= x/1[/itex] and thus [itex]\arcsin(x)= \theta[/itex].

Now, what is the length of the near side and what is [itex]tan(\theta)= tan(arcsin(x))[/itex]?

You are missing a square in your answer.