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Ex 2.5, 9 (i) - Chapter 2 Class 9 Polynomials (Term 2)
Last updated at Aug. 25, 2021 by Teachoo
Ex 2.5
Ex 2.5, 1 (i)
Ex 2.5, 1 (ii)
Ex 2.5, 1 (iii) Important
Ex 2.5, 1 (iv)
Ex 2.5, 1 (v)
Ex 2.5, 2 (i)
Ex 2.5, 2 (ii) Important
Ex 2.5, 2 (iii)
Ex 2.5, 3 (i)
Ex 2.5, 3 (ii) Important
Ex 2.5, 3 (iii)
Ex 2.5, 4 (i)
Ex 2.5, 4 (ii)
Ex 2.5, 4 (iii) Important
Ex 2.5, 4 (iv)
Ex 2.5, 4 (v)
Ex 2.5, 4 (vi)
Ex 2.5, 5 (i)
Ex 2.5, 5 (ii) Important
Ex 2.5, 6 (i)
Ex 2.5, 6 (ii)
Ex 2.5, 6 (iii)
Ex 2.5, 6 (iv) Important
Ex 2.5, 7 (i)
Ex 2.5, 7 (ii)
Ex 2.5, 7 (iii) Important
Ex 2.5, 8 (i)
Ex 2.5, 8 (ii)
Ex 2.5, 8 (iii) Important
Ex 2.5, 8 (iv) Important
Ex 2.5, 8 (v)
Ex 2.5, 9 (i) You are here
Ex 2.5, 9 (ii)
Ex 2.5, 10 (i) Important
Ex 2.5, 10 (ii)
Ex 2.5, 11
Ex 2.5,12 Important
Ex 2.5,13
Ex 2.5, 14 (i)
Ex 2.5, 14 (ii) Important
Ex 2.5, 15 (i)
Ex 2.5, 15 (ii) Important
Ex 2.5, 16 (i)
Ex 2.5, 16 (ii) Important
Transcript
Ex 2.5, 9 Verify: (i) x3 + y3 = (x + y) (x2 – xy + y2) L.H.S x3 + y3 We know (x + y)3 = x3 + y3 + 3xy (x + y) So, x3 + y3 = (x + y)3 – 3xy (x + y) = (x + y)3 – 3xy (x + y) = (x + y) [ (x + y)2 – 3xy)] Using (a+b)2 = a2 + b2 + 2ab = (x + y) [(x2 + y2 + 2xy) – 3xy] = (x + y) (x2 + y2 – xy) = (x + y) (x2 - xy + y2) = R.H.S R.H.S (x + y) (x2 – xy + y2) Hence proved
