Ex 2.4, 4 (iv) - Chapter 2 Class 9 Polynomials

Last updated at August 14, 2026 by

Ex 2.4, 4 (iv) - Expand (3a - 7b - c)^2 using suitable identities - Ex 2.4

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Ex 2.4, 4 Expand each of the following, using suitable identities: (iv) (3a 7b c)2 (3a 7b c)2 = (3a + ( 7b) + ( c) )2 Using (x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx x = 3a, y = -7b , z = -c = (3a)2 + (-7b)2 + (-c)2 + 2(3a)(-7b) + 2(-7b)(-c) + 2(-c) (3a) = 9a2 + 49b2 + c2 42ab + 14bc 6ac

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