Derivative of sin^-1(x) on Interval [1,-1] with Solution Attempt

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The discussion focuses on computing the derivative of the function f(x) = sin^-1(x) over the interval [1, -1]. The derivative is initially stated as f'(x) = 1/[sqrt(1-x^2)], but there is confusion regarding the relevance of the interval [-π/2, π/2]. Implicit differentiation is suggested as a method to derive the formula, leading to dy/dx = 1/cos(sin^-1(x)), which can be simplified further. The mention of the Greek letter π clarifies a common misconception about its pronunciation. Understanding the derivative and its application within the specified intervals is essential for solving the problem.
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Homework Statement



Compute the derivative of the following function.

Homework Equations



f:[1,-1] arrow [-pie/2, pie/2] given by f(x)=sin^-1 (x)

The Attempt at a Solution



I know that f ' (x)=1/[sqrt(1-x^2)]

Im not sure how to include the intervals of pie given, not sure what they want me to do.
 
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Knowing what the derivative is doesn't do you much good if you have compute it.

Do you know about implicit differentiation?

If so, letting y = f(x), you have y = sin-1(x)
Solve this equation for x, and then calculate dy/dx.

When you do this, you should get dy/dx = 1/cos(sin-1(x)), which you can simplify further. That's where the interval [-pi, pi] comes into play.

BTW, the name of the Greek letter \pi is pi, not pie.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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