Q. Evaluate the integral and express your answer in simplest form.∫xx2−25−9dxAnswer:
Identify Integral: Let's identify the integral we need to evaluate:I=∫xx2−25−9dxTo solve this integral, we can use a trigonometric substitution. Let x=5sec(θ), which implies dx=5sec(θ)tan(θ)dθ. When x=5sec(θ), x2−25 becomes 25sec2(θ)−25=5tan(θ).
Trigonometric Substitution: Substitute x=5sec(θ) and dx=5sec(θ)tan(θ)dθ into the integral:I=∫5sec(θ)∗5tan(θ)−9∗5sec(θ)tan(θ)dθSimplify the integral:I=∫5−9dθ
Substitute and Simplify: Integrate with respect to θ:I=(−59)θ+C, where C is the constant of integration.
Integrate with Respect: Now we need to express θ in terms of x to get back to the original variable. From x=5sec(θ), we have sec(θ)=5x. Taking the arccosine of both sides, we get θ=sec−1(5x).
Express in Terms of x: Substitute θ back into the integral result: I=(−59)sec−1(5x)+C This is the simplest form of the integral in terms of x.
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