// Numbas version: finer_feedback_settings {"name": "Integrating Hyperbolics 3&4 combined", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Integrating Hyperbolics 3&4 combined", "tags": [], "metadata": {"description": "
Rearrange and make a substitution to integrate a quotient to a function in terms of arsinh.
", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "statement": "Rearrange and make an appropriate substitutions to evaluate the following integrals.
\nDon't forget to include '$+C$'!
", "advice": "We will be using the identity
\n$\\int \\simplify{1/sqrt(x^2 + a^2)} \\, dx = \\simplify{arsinh(x/a)} + c$
\nTherefore, we have
\n$\\begin{aligned}
y &= \\int \\simplify{1/sqrt(x^2 + {2a}x + {a^2} + {b^2})} \\,dx \\\\
&= \\int \\simplify{1/sqrt((x + {a})^2 + {b^2})} \\, dx \\\\
\\end{aligned}$
We can then set $u = x + \\var{a}$ and $a = \\var{b}$ and have
\n$\\begin{aligned}
y &= \\int \\simplify{1/sqrt(x^2 + {2a}x + {a^2} + {b^2})} \\, dx \\\\
&= \\int \\simplify{1/sqrt(u^2 + a^2)} \\, dx \\\\
&= \\simplify{arsinh(u/a) + c} \\\\
&= \\simplify{arsinh((x+{a})/{b}) + c}
\\end{aligned}$
$
\\int \\simplify{1/sqrt(x^2 + {2a}x + {a^2} + {b^2})} \\, dx = $ [[0]]
$\\int \\simplify{sqrt({a}x^2 + {b})} \\, dx =$[[0]]
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