# Science:Math Exam Resources/Courses/MATH101/April 2017/Question 02 (b)

MATH101 April 2017
Other MATH101 Exams

### Question 02 (b)

Which of the following substitutions is most helpful in evaluating the integral ${\displaystyle \int _{2}^{4}{\frac {dx}{x^{2}{\sqrt {x^{2}+2x+10}}}}}$?

F: ${\displaystyle x={\sqrt {10}}\tan u}$

G: ${\displaystyle u=x^{2}+2x+10}$

H: ${\displaystyle u=x^{2}}$

J: ${\displaystyle x=3\sec u-1}$

K: ${\displaystyle x=3\tan u-1}$

L: ${\displaystyle x={\sqrt {10}}\sec u}$

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