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0580/13 Oct/Nov 2021, Question 23: Index Laws with Letters

Cambridge IGCSE Mathematics 0580 · Paper 13 (Core) · Calculator · 6 marks

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The question, in short

Simplify an algebraic division, factorise a two-term expression completely, and expand and simplify a product of two binomials.

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

Part (a) · 2 marks

Simplify 32g³² ÷ 4g⁴.

  1. 132 ÷ 4 = 8, g³² ÷ g⁴ = g³²⁻⁴ = g²⁸
  2. 2= 8g²⁸

Answer8g²⁸

Part (b) · 2 marks

Factorise 10j − 15j² completely.

  1. 1HCF of 10j and 15j² is 5j
  2. 210j − 15j² = 5j(2 − 3j)

Answer5j(2 − 3j)

Part (c) · 2 marks

Expand and simplify (x + 7)(x + 3).

  1. 1(x + 7)(x + 3) = x² + 3x + 7x + 21
  2. 2= x² + 10x + 21

Answerx² + 10x + 21

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Also searched as: 0580/13/O/N/21 · 0580_w21_qp_13 · 0580 w21 13 · question 23.
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