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Ch. 3 - Derivatives
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Not the one you use?Change textbook
Chapter 3, Problem 3.8.19a

13-26 Implicit differentiation Carry out the following steps.
a. Use implicit differentiation to find dy/dx.
cos y = x; (0, π/2)

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Start by differentiating both sides of the equation with respect to x. The equation is cos(y) = x.
Differentiate the left side: The derivative of cos(y) with respect to x is -sin(y) * (dy/dx) because of the chain rule.
Differentiate the right side: The derivative of x with respect to x is 1.
Set the derivatives equal to each other: -sin(y) * (dy/dx) = 1.
Solve for dy/dx by isolating it: dy/dx = -1/sin(y).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Implicit Differentiation

Implicit differentiation is a technique used to differentiate equations where the dependent and independent variables are not explicitly separated. Instead of solving for y in terms of x, we differentiate both sides of the equation with respect to x, treating y as a function of x. This method is particularly useful for equations that are difficult or impossible to rearrange.
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Finding The Implicit Derivative

Chain Rule

The chain rule is a fundamental principle in calculus that allows us to differentiate composite functions. When using implicit differentiation, the chain rule is applied to account for the derivative of y with respect to x, denoted as dy/dx. This means that when differentiating a function of y, we multiply by dy/dx to reflect the dependence of y on x.
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Intro to the Chain Rule

Trigonometric Functions

Trigonometric functions, such as sine, cosine, and tangent, are essential in calculus for modeling periodic phenomena and solving various problems. In the context of the given equation, cos(y) = x, understanding the properties and derivatives of these functions is crucial for finding dy/dx. The derivative of cos(y) involves the chain rule and is equal to -sin(y) * dy/dx.
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