Derivative of Inverse Trig Function: y=4*arcsin(x/4)

In summary, we are finding the derivative of a function that involves an inverse trigonometric function, specifically the inverse sine function. We follow the standard process of solving for the derivative by differentiating both sides of the equation and solving for \frac{dy}{dx}. We end up with a final expression involving the inverse cosine function and the given function.
  • #1
MarkFL
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Here is the question:

Derivative of Inverse Function?


Find d/dx of y = 4*arcsin(x/4)

I have posted a link there to this thread so the OP can see my work.
 
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  • #2
Hello harpazo,

We are given:

\(\displaystyle y=4\sin^{-1}\left(\frac{x}{4} \right)\)

which implies:

\(\displaystyle \sin\left(\frac{y}{4} \right)=\frac{x}{4}\)

Differentiating with respect to $y$, we obtain:

\(\displaystyle \frac{1}{4}\cos\left(\frac{y}{4} \right)=\frac{1}{4}\frac{dx}{dy}\)

Solving for \(\displaystyle \frac{dy}{dx}\), we get:

\(\displaystyle \frac{dy}{dx}=\sec\left(\frac{y}{4} \right)\)

Since \(\displaystyle \frac{y}{4}=\sin^{-1}\left(\frac{x}{4} \right)\) we have:

\(\displaystyle \frac{dy}{dx}=\sec\left(\sin^{-1}\left(\frac{x}{4} \right) \right)=\frac{4}{\sqrt{16-x^2}}\)
 

FAQ: Derivative of Inverse Trig Function: y=4*arcsin(x/4)

What is the derivative of the inverse sine function?

The derivative of the inverse sine function is equal to the reciprocal of the square root of 1 minus x squared, or 1/√(1-x^2).

How do you find the derivative of an inverse trigonometric function?

To find the derivative of an inverse trigonometric function, use the chain rule and the derivative of the corresponding trigonometric function. In this case, the derivative of arcsin(x) is 1/√(1-x^2).

What is the derivative of y=4*arcsin(x/4)?

The derivative of y=4*arcsin(x/4) is 4/√(16-x^2).

Can you simplify the derivative of y=4*arcsin(x/4)?

Yes, the derivative can be simplified to 1/√(1-(x/4)^2).

How do you use the derivative of an inverse trigonometric function to find the slope of a curve?

The derivative of an inverse trigonometric function can be used to find the slope of a curve at a specific point. Simply plug in the x-coordinate of the point into the derivative function to find the slope at that point.

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