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Simplifying an expression of the form $a^3 \\times (a^4)^{1/2}$ to $a^5$, where $a$ is an integer. 

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Without a calculator, simplify the following expression into a single integer:

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\\[ \\var{a}^3 \\times \\var{a^4}^{1/2}\\]

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To simplify $\\var{a}^3 \\times \\var{a^4}^{1/2}$, we want to make use of the following 2 rules:

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  1. $\\left(a^n\\right)^m =a^{n\\times m}$;
  2. \n
  3. $a^n \\times a^m = a^{n+m}$.
  4. \n
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Notice that we can rewrite this expression so that both numbers are in terms of $\\var{a}$, since $\\var{a^4} = \\var{a}^4$:

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\\[\\var{a}^3 \\times \\var{a^4}^{1/2} = \\var{a}^3 \\times \\left(\\var{a}^4\\right)^{1/2}.\\]

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Applying rule 1 to the second term:

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\\[ \\begin{split} \\var{a}^3 \\times \\left(\\var{a}^4\\right)^{1/2} &\\,= \\var{a}^3 \\times \\var{a}^{4 \\times 1/2} \\\\ &\\,= \\var{a}^3 \\times \\var{a}^2. \\end{split} \\]

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Then applying rule 2:

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\\[\\var{a}^3 \\times \\var{a}^2 = \\var{a}^5.\\]

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Therefore, 

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\\[ \\begin{split} \\var{a}^3 \\times \\var{a^4}^{1/2} &\\,= \\var{a}^5 \\\\ &\\,= \\var{a^5}. \\end{split} \\]

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