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Factorise the followinga. b square m + b square nb. 54x square y + 24 xyc. 6ab +6bc |
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Answer» Step-by-step explanation: Factoring Polynomials Examples - Examples Question 1 : Factorise the following expressions: (i) 2a2 + 4a2 b + 8a2 c Solution : = 2a2 + 4a2 b + 8a2 c By factoring 2a from the three terms, we get = 2a (a + 2ab + 4ac) (ii) ab - ac - MB + mc Solution : = ab - ac - mb + mc = a(b - c) - m(b - c) = (a - m) (b - c) Question 2 : Factorise the following: (i) x2 + 4x + 4 Solution : = x2 + 4x + 4 = x2 + 2 ⋅ x ⋅ 2 + 22 = (x + 2)2 (ii) 3a2 - 24ab + 48b2 Solution : = 3a2 - 24ab + 48b2 = 3 (A2 - 8ab + 16b2) = 3 [a2 - 2a(4b) + (4b)2] = 3 (a - 4b)2 (iii) x5 - 16x Solution : = x5 - 16x = x(x4 - 16) = x [(x2)2 - 42] = x(x2 + 4)(x2 - 4) = x(x2 + 4)(x + 2)(x - 2) (iv) m2 + 1/m2 - 23 Solution : m2 + 1/m2 - 23 = m2 + 1/m2 - 25 + 2 = (m2 + 1/m2 + 2) - 25 = (m + (1/m))2 - 52 = (m + (1/m) + 5) (m + (1/m) - 5) (v) 6 - 216 x2 Solution : = 6 - 216 x2 = 6(1 - 36x2) = 6[1 - (6X)2] = 6(1 + 6x)(1 - 6x) (vi) a2 + 1/a2 - 18 Solution : a2 + 1/a2 - 18 = a2 + 1/a2 - 16 - 2 = (a2 + 1/a2 - 2) - 16 = (a - (1/a))2 - 42 = (a + (1/a) + 4) (a + (1/a) - 4) |
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