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WMA11/01 Jan 2020, Question 2: Powers with Letters in the Exponent

Pearson Edexcel International AS Level Mathematics · Pure Mathematics 1 (WMA11) · Calculator · 5 marks

The question, in short

Using y = 3ˣ, rewrite three index expressions purely in terms of y, giving each in its simplest form.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (a) · 1 mark

Express 3³ˣ in terms of y, simplified.

  1. 13³ˣ = (3ˣ)³
  2. 2= y³

Answery³

Part (b) · 2 marks

Express 1/3ˣ⁻² in terms of y, simplified.

  1. 11/3ˣ⁻² = 3²/3ˣ
  2. 2= 9/y

Answer9/y

Part (c) · 2 marks

Express 81/9²⁻³ˣ in terms of y, simplified.

  1. 181/9²⁻³ˣ = 9²/9²⁻³ˣ = 9³ˣ
  2. 29³ˣ = 3⁶ˣ = (3ˣ)⁶ = y⁶

Answery⁶

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Also searched as: WMA11 January 2020 · WMA11/01 · wma11 jan20 · IAS Maths Pure Mathematics 1 January 2020 · question 2.
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