Ex 12.2, 3 (ii) - Chapter 12 Class 8 Factorisation

Last updated at August 13, 2026 by

Ex 12.2, 3 (ii) - Factorise 7p^2 + 21q^2 - Chapter 14 Class 8 NCERT - Ex 12.2

part 2 - Ex 12.2, 3 (ii) - Ex 12.2 - Serial order wise - Chapter 12 Class 8 Factorisation

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Ex 12.2, 3 (Method 1) Factorise the expressions. (ii) 7〖𝑝 〗^2 + 21𝑞^27〖p 〗^2 + 21q^2 = 7〖p 〗^2 + (7 × 3) 〖q 〗^2 Taking 7 Common, = 7 (𝒑^𝟐 + 3𝒒^𝟐) Ex 12.2, 3 (Method 2) Factorise the expressions. (ii) 7〖𝑝 〗^2 + 21𝑞^27〖p 〗^2 21𝑞^2 So, 7 is the only common factor. 7〖𝑝 〗^2 + 21𝑞^2 = (7 × p × p) + (3 × 7 × q × q) Taking 7 Common, = 7 × ((p × p) + (3 × q × q)) = 7 × (p^2 + 3q^2) = 7 (𝒑^𝟐 + 3𝒒^𝟐) = 7 × 〖p 〗^2 = 21 × 𝑞^2 = 7 × p × p = 3 × 7 × q × q = 3 × 7 × q × q

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