Substitution and Simplification: Now, we substitute x=7sec(θ) and dx=7sec(θ)tan(θ)dθ into the integral:I=∫x2−7xdxI=∫72sec2(θ)−77sec(θ)(7sec(θ)tan(θ)dθ)
Further Simplification: Simplify the expression inside the square root and the integral:I=∫72(sec2(θ)−1)7sec(θ)(7sec(θ)tan(θ)dθ)I=∫72tan2(θ)7sec(θ)(7sec(θ)tan(θ)dθ)
Integration: Since tan2(θ) is the result of sec2(θ)−1, we can further simplify the integral:I=∫7tan(θ)7sec(θ)(7sec(θ)tan(θ)dθ)I=∫sec2(θ)tan(θ)dθ
Integration of sec2(θ)tan(θ): Now, we can integrate sec2(θ)tan(θ) with respect to θ: I=∫(sec2(θ)tan(θ)dθ)I=2sec(θ)+C, where C is the constant of integration.
Reverting to Original Variable: We need to revert back to the original variable x. From our substitution, we have x=7sec(θ), so sec(θ)=7x. Substituting this back into our integral gives us:I=2(7x)+CI=27x+C
Final Indefinite Integral: Finally, we have the indefinite integral of the function f(x)=x2−7x in terms of x:I=27x+C
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