Help with inverse trig functions

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Homework Help Overview

The discussion revolves around the evaluation of the expression cot(arcsin(x)), which involves inverse trigonometric functions and their relationships within a right triangle context.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore the relationship between cotangent and arcsine by suggesting the use of a right triangle to define the sides based on the angle θ = arcsin(x). There are questions about the correctness of the original poster's expression and the need for clarity in notation.

Discussion Status

Some participants have offered guidance on how to approach the problem by visualizing a right triangle and labeling the sides. There is an acknowledgment of a potential error in the original poster's answer, specifically regarding the missing square in their expression.

Contextual Notes

Participants note that the original poster's notation may lead to confusion and emphasize the importance of clear mathematical communication. There is also a mention of an online program providing feedback that the original answer is incorrect.

vysero
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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.
 
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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.
 

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