OCR MEI C2 2011 January — Question 7 4 marks

Exam BoardOCR MEI
ModuleC2 (Core Mathematics 2)
Year2011
SessionJanuary
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicLaws of Logarithms
TypeEvaluate log expression using laws
DifficultyEasy -1.3 This is a straightforward application of basic logarithm laws (power rule and subtraction rule) with no problem-solving required. Both parts are direct one-step simplifications using standard rules that students practice routinely, making it easier than average.
Spec1.06f Laws of logarithms: addition, subtraction, power rules

7 Simplify
  1. \(\log _ { 10 } x ^ { 5 } + 3 \log _ { 10 } x ^ { 4 }\),
  2. \(\log _ { a } 1 - \log _ { a } a ^ { b }\).

Question 7:
AnswerMarks Guidance
AnswerMark Guidance
(i) \(17\log_{10}x\) or \(\log_{10}x^{17}\)B2 M1 for \(5\log_{10}x\) or \(12\log_{10}x\) or \(\log_{10}x^{12}\) as part of the first step
(ii) \(-b\)B2 M1 for \(\log_a 1 = 0\) or \(\log_a a = 1\) soi
**Question 7:**

| Answer | Mark | Guidance |
|--------|------|----------|
| (i) $17\log_{10}x$ or $\log_{10}x^{17}$ | **B2** | **M1** for $5\log_{10}x$ or $12\log_{10}x$ or $\log_{10}x^{12}$ as part of the first step | condone omission of base |
| (ii) $-b$ | **B2** | **M1** for $\log_a 1 = 0$ or $\log_a a = 1$ soi | allow $0-b$ |

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7 Simplify\\
(i) $\log _ { 10 } x ^ { 5 } + 3 \log _ { 10 } x ^ { 4 }$,\\
(ii) $\log _ { a } 1 - \log _ { a } a ^ { b }$.

\hfill \mbox{\textit{OCR MEI C2 2011 Q7 [4]}}