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Here is a table of the derivatives of some of the hyperbolic functions:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n
$f(x)$$\\displaystyle{\\frac{df}{dx}}$
$\\sinh(bx)$$b\\cosh(bx)$
$\\cosh(bx)$$b\\sinh(bx)$
$\\tanh(bx)$$\\simplify{b*sech(bx)^2}$
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a)

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$f(x)=\\simplify[std]{ x ^ {n} * sinh({a1} * x + {b1})}$

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Use the product rule to obtain:
\\[\\frac{df}{dx} = \\simplify[std]{{n} * (x ^ {(n -1)}) * sinh({a1} * x + {b1}) + {a1} * (x ^ {n}) * Cosh({a1} * x + {b1})}\\]

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b)

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$f(x)=\\tanh(\\simplify[std]{{a}x+{b}})$

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Using the table above we get:
\\[\\frac{df}{dx} = \\simplify[std]{{a}*sech({a}x+{b})^2}\\]

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c)

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$f(x)=\\ln(\\cosh(\\simplify[std]{{a2}x+{b2}}))$

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Using the chain rule we find:

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\\[\\frac{df}{dx} = \\simplify[std]{{a2} * tanh({a2} * x + {b2})}\\]

\n \n \n \n ", "rulesets": {"std": ["all", "fractionNumbers", "!collectNumbers", "!noLeadingMinus"]}, "parts": [{"prompt": "\n

$f(x)=\\simplify[std]{ x ^ {n} * sinh({a1} * x + {b1})}$

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$\\displaystyle{\\frac{df}{dx}=\\;\\;}$[[0]]

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$f(x)=\\tanh(\\simplify[std]{{a}x+{b}})$

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$\\displaystyle{\\frac{df}{dx}=\\;\\;}$[[0]]

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$f(x)=\\ln(\\cosh(\\simplify[std]{{a2}x+{b2}}))$

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$\\displaystyle{\\frac{df}{dx}=\\;\\;}$[[0]]

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Write down the derivatives of the following functions $f(x)$ .

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Note that in order to input the square of a function such as $\\sinh(x)$ you have to input it as $(\\sinh(x))^2$, similarly for the other hyperbolic functions.

\n \n \n \n ", "variable_groups": [], "progress": "ready", "type": "question", "variables": {"a": {"definition": "random(2..9)", "name": "a"}, "b": {"definition": "random(-9..9)", "name": "b"}, "n": {"definition": "random(3..7)", "name": "n"}, "a1": {"definition": "random(-9..-1)", "name": "a1"}, "a2": {"definition": "random(2..9)", "name": "a2"}, "b1": {"definition": "random(1..9)", "name": "b1"}, "b2": {"definition": "random(-9..9)", "name": "b2"}}, "metadata": {"notes": "\n \t\t

29/06/2012:

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Added and edited tags.

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19/07/2012:

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Added description.

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There is also the problem of inputting functions of the form $xf(x)$ if $n=1$ or $2$ in the first question. So have reset $n$ to between $3$ and $7$. Otherwise would have to have an instruction here (perhaps depending on value of $n$).

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Checked calculation.

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23/07/2012:

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Added tags.

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Question appears to be working correctly.

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1/08/2012:

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This is a copy of MAS114220122013CBA3_4 and is included in Diagnostic: Chain Rule Practice exam.

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Differentiate the following functions: $\\displaystyle x ^ n \\sinh(ax + b),\\;\\tanh(cx+d),\\;\\ln(\\cosh(px+q))$

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