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What change of variables is suggested by an integral containing √(100-x²)

User Maayan
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Final answer:

A trigonometric substitution such as x = 10sin(θ) or x = 10cos(θ) is suggested for an integral containing the expression √(100-x²), because it simplifies the square root and facilitates easier integration using standard trigonometric integrals.

Step-by-step explanation:

For an integral containing the expression √(100-x²), the suggested change of variables would be to use a trigonometric substitution. Specifically, you could use the substitution x = 10sin(θ) or x = 10cos(θ), which simplifies the square root based on the identity sin²(θ) + cos²(θ) = 1. This change of variables will transform the integral into a form that involves trigonometric functions, which are generally easier to integrate.

In this case, if we choose x = 10sin(θ), then dx = 10cos(θ)dθ. Substituting these into the integral will give us an integral in terms of θ, which does not contain any square roots and can be evaluated using standard trigonometric integrals.

User Uday Kiran
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