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HELM Book 1.2.2 exercises

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Use the index laws to simplify 3 simple expressions;

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n^a*n^b, n^a/n^b, (n^a)^b, where n is a randomised variable or number, and a and b are randomised nonzero integers.

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Part of HELM Book 1.2

", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "

Rewrite each of the following expressions with a single index. In each case, write the value of the index in the box.

", "advice": "

(a)

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\\[\\var{abase}^\\var{ex1_idx[0]}\\var{abase}^\\var{ex1_idx[1]}=\\var{abase}^{(\\var{ex1_idx[0]})+(\\var{ex1_idx[1]})}=\\var{abase}^{\\var{ex1_idx[0]+ex1_idx[1]}}\\]

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(b)

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\\[\\frac{\\var{bbase}^\\var{ex1_idx[2]}}{\\var{bbase}^\\var{ex1_idx[3]}}=\\var{bbase}^{(\\var{ex1_idx[2]})-(\\var{ex1_idx[3]})}= \\var{bbase}^{\\var{ex1_idx[2]-ex1_idx[3]} } \\]

\n

(c)

\n

\\[\\left(\\var{cbase}^\\var{ex1_idx[4]}\\right)^\\var{ex1_idx[5]}=\\var{cbase}^{(\\var{ex1_idx[4]})\\times (\\var{ex1_idx[5]}) }=\\var{cbase}^{\\var{ex1_idx[4]*ex1_idx[5]} } \\]

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(m^7)^-5 is not accepting 1/m^35 as an answer, but it does accept m^-35

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(a) $\\var{abase}^\\var{ex1_idx[0]}$ $\\var{abase}^\\var{ex1_idx[1]} =  \\var{abase}^u$, where $u=$[[0]]

\n

(b) $\\frac{\\var{bbase}^\\var{ex1_idx[2]}}{\\var{bbase}^\\var{ex1_idx[3]}} = \\var{bbase}^u$, where $u=$[[1]]

\n

(c) $\\left(\\var{cbase}^\\var{ex1_idx[4]}\\right)^\\var{ex1_idx[5]} = \\var{cbase}^u$, where $u=$[[2]]

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Remove the brackets from (na)^k, or from n(a)^kwhere n is a number and a is a variable.

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Part of HELM Book 1.2

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Remove the brackets from $\\var{expr}$.

", "advice": "

\\[\\var{expr}=\\var{c}\\var{ve[0]}^{\\var{idx}}\\var{ve[1]}^{\\var{idx}}\\]

\n

\\[\\var{expr}=\\var{c}^{\\var{idx}}\\var{ve[0]}^{\\var{idx}}\\]

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\\[\\var{expr}=\\var{c}^{\\var{idx}}\\var{ve[0]}^{\\var{idx}}\\var{ve[1]}^{\\var{idx}}\\]

\n

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number of variables to include.

\n

If nv=0 then 2 variables are used and the constant is not powered.

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for display in the advice

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Simplify n1.v^k1.(n2.v^k2), where n1, n2 are positive integers, v is a random letter variable, and k1 and k2 are nonzero integers.

\n

The answer should be expressed as n.v^k

\n

Part of HELM Book 1.2

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Simplify $\\var{c[0]}\\var{v}^\\var{idx[0]}(\\var{c[1]}\\var{v}^\\var{idx[1]})$

", "advice": "

\\[\\begin{align*}\\var{c[0]}\\var{v}^\\var{idx[0]}(\\var{c[1]}\\var{v}^\\var{idx[1]})&= \\var{c[0]}\\times\\var{c[1]}\\times\\var{ve}^{\\var{idx[0]}}\\times\\var{ve}^{\\var{idx[1]}}\\\\ &=\\var{c[0]*c[1]}\\var{ve}^{(\\var{idx[0]})+(\\var{idx[1]})}\\\\ &=\\var{expr} \\end{align*}\\]

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the variable to use

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for display purposes in the advice.

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You need to write the expression as a single number times the variable to a single power.", "nameToCompare": ""}, "valuegenerators": []}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always"}]}], "allowPrinting": true, "navigation": {"allowregen": true, "reverse": true, "browse": true, "allowsteps": true, "showfrontpage": true, "showresultspage": "oncompletion", "navigatemode": "menu", "onleave": {"action": "none", "message": ""}, "preventleave": true, "startpassword": "", "allowAttemptDownload": false, "downloadEncryptionKey": ""}, "timing": {"allowPause": true, "timeout": {"action": "none", "message": ""}, "timedwarning": {"action": "none", "message": ""}}, "feedback": {"showactualmark": true, "showtotalmark": true, "showanswerstate": true, "allowrevealanswer": true, "advicethreshold": 0, "intro": "

Work through these practice questions. You can try each question as many times as you like. The numbers will change each time. Some of the questions are randomly chosen, so if you re-open this set of exercises you may see some different questions.

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