Q92Multiple choice
Factorise the following using the identity a2 – b 2 = (a a+b a – b ). b) (a
- (i)x2 – 9
- (ii)4x2 – 25y2
- (iii)4x2 – 49y2
- (iv)3a2b3 – 27a4b (v) 28ay2 – 175ax2 (vi) 9x2 – 1 x 2 y2 (vii) 25ax2 – 25a (viii) − 9 25 2p 2 (ix) – 32q 2 (x) 49x2 – 36y2 y x2 (xi) y3 – (xii) – 625 9 25 x2 y2 4x 2 9y 2 (xiii) − (xiv) − 8 18 9 16 x 3y xy 3 (xv) − (xvi) 1331x3y – 11y3x 9 16 1 2 2 16 2 2 (xvii) a b – b c (xviii) a4 – (a – b)4 36 49 (xix) x4 – 1 (xx) y4 – 625 (xxi) p5 – 16p (xxii) 16x4 – 81 (xxiii) x4 – y4 (xxiv) y4 – 81 (xxv) 16x4 – 625y4 (xxvi) (a – b)2 – (b – c)2 (xxvii) (x + y)4 – (x – y)4 (xxviii) x4 – y4 + x2 – y2 3 2 y2 (xxix) 8a – 2a (xxx) x – (xxxi) 9x2 – (3y + z)2
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(i) x2 – 9
(ii) 4x2 – 25y2
(iii) 4x2 – 49y2
(iv) 3a2b3 – 27a4b (v) 28ay2 – 175ax2 (vi) 9x2 – 1 x 2 y2 (vii) 25ax2 – 25a (viii) − 9 25 2p 2 (ix) – 32q 2 (x) 49x2 – 36y2 y x2 (xi) y3 – (xii) – 625 9 25 x2 y2 4x 2 9y 2 (xiii) − (xiv) − 8 18 9 16 x 3y xy 3 (xv) − (xvi) 1331x3y – 11y3x 9 16 1 2 2 16 2 2 (xvii) a b – b c (xviii) a4 – (a – b)4 36 49 (xix) x4 – 1 (xx) y4 – 625 (xxi) p5 – 16p (xxii) 16x4 – 81 (xxiii) x4 – y4 (xxiv) y4 – 81 (xxv) 16x4 – 625y4 (xxvi) (a – b)2 – (b – c)2 (xxvii) (x + y)4 – (x – y)4 (xxviii) x4 – y4 + x2 – y2 3 2 y2 (xxix) 8a – 2a (xxx) x – (xxxi) 9x2 – (3y + z)2