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What can be said about the value of $C_i$?
\n$C_0=$ [[0]], $C_1=$ [[1]], $C_2=$ [[2]], $C_3=$ [[3]], $C_4=$ [[4]], $C_5=$ [[5]]
", "sortAnswers": false, "variableReplacementStrategy": "originalfirst", "type": "gapfill"}], "advice": "Two polynomials are equal if and only if their corresponding coefficients are also equal.
\nSo we 'equate the coefficients' of the polynomials given in this question, this means that the constant terms must be equal, ie
\n\\[\\simplify{{k[0]}=C_0+{j[0]}}\\]
\nthe coefficients of the $x$ terms must be equal, ie
\n\\[\\simplify{{k[1]}={j[1]}C_1+{j[2]}}\\]
\nthe coefficients of the $x^2$ terms must be equal, ie
\n\\[\\simplify{{k[2]}=C_2}\\]
\nthe coefficients of the $x^3$ terms must be equal, ie
\n\\[\\simplify{{k[3]}={j[3]}C_3}\\]
\nthe coefficients of the $x^4$ terms must be equal, ie
\n\\[\\simplify{{k[4]}=C_4/{j[4]}}\\]
\nand the coefficients of the $x^5$ terms must be equal, ie
\n\\[\\simplify{{k[5]}=C_5/{j[5]}+{j[6]}}.\\]
\nSolving equal of these equations for $C_i$ gives our required values.
", "tags": ["l4", "L4"], "preamble": {"css": "", "js": ""}, "metadata": {"description": "Equating coefficients of a polynomial. Basic ones that don't require simultaneous equations.
", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "ungrouped_variables": ["k", "n", "poly", "otherpoly", "j"], "statement": "Suppose that during some working, you find that
\n{poly} $=$ {otherpoly}
\nfor all $x$.
", "name": "Polynomials: equating coefficients 1 [L4 Randomised]", "functions": {}, "type": "question", "contributors": [{"name": "Ben Brawn", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/605/"}, {"name": "Paul Hancock", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1738/"}, {"name": "Abbi Mullins", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2466/"}, {"name": "Matthew James Sykes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2582/"}]}]}], "contributors": [{"name": "Ben Brawn", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/605/"}, {"name": "Paul Hancock", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1738/"}, {"name": "Abbi Mullins", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2466/"}, {"name": "Matthew James Sykes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2582/"}]}