Download, print and study this document offline |
Page 1 Question: Divide: (i) 24xy 2 z 3 by 6yz 2 (ii) 63a 2 b 4 c 6 by 7a 2 b 2 c 3 Solution: (i) We have 24xy 2 z 3 ? 6yz 2 = 24 6 23 2 xy z yz = 222 3 23 ¥ ¥ ¥ ¥¥ ¥¥ ¥ ¥ ¥¥ ¥¥¥ x yyz zz yz z = 22 1 ¥¥ ¥ ¥ xyz \ 24xy 2 x 3 ? 6yz 2 = 4xyz (ii) 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 63a b c 7a b c 24 6 22 3 = 33 7 7 24 6 22 3 ¥¥ ¥ ¥ ¥ ¥¥ ¥ ab c ab c = 3 ¥ 3 ¥ a a 2 2 ¥ b b 4 2 ¥ c c 6 3 = 9 ¥ a 2–2 ¥ b 4– 2 c 6–3 Page 2 Question: Divide: (i) 24xy 2 z 3 by 6yz 2 (ii) 63a 2 b 4 c 6 by 7a 2 b 2 c 3 Solution: (i) We have 24xy 2 z 3 ? 6yz 2 = 24 6 23 2 xy z yz = 222 3 23 ¥ ¥ ¥ ¥¥ ¥¥ ¥ ¥ ¥¥ ¥¥¥ x yyz zz yz z = 22 1 ¥¥ ¥ ¥ xyz \ 24xy 2 x 3 ? 6yz 2 = 4xyz (ii) 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 63a b c 7a b c 24 6 22 3 = 33 7 7 24 6 22 3 ¥¥ ¥ ¥ ¥ ¥¥ ¥ ab c ab c = 3 ¥ 3 ¥ a a 2 2 ¥ b b 4 2 ¥ c c 6 3 = 9 ¥ a 2–2 ¥ b 4– 2 c 6–3 = 9 ¥ a 0 + b 2 ¥ c 3 = 9 ¥ 1 ¥ b 2 ¥ c 3 = 9b 2 c 3 \ 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 9b 3 c 3 EXERCISE 14.3 Question 1. Carry out the following divisions. (i) 28x 4 ? 56x (ii) –36y 3 ? 9y 2 (iii) 66pq 2 r 3 ? 11qr 2 (iv) 34x 3 y 3 z 3 ? 51xy 2 z 3 (v) 12a 8 b 8 ? (–6a 6 b 4 ) Solution: (i) We have 28x 4 ? 56x = 28 56 4 x x = 227 22 2 7 4 1 ¥¥ ¥ ¥ ¥¥¥ x x = 1 2 ¥ x 4– 1 = 1 2 x 3 \ 28x 4 ? 56x = 1 2 x 3 (ii) We have –36y 3 = (–1) ¥ 2 ¥ 2 ¥ 3 ¥ 3 ¥ y ¥ y ¥ y and 9y 2 = 3 ¥ 3 ¥ y ¥ y \ –36y 3 ? 9y 2 = -36 9 3 2 y y = () - ¥¥¥ ¥ ¥ ¥ ¥ ¥¥ ¥ 12 2 3 3 33 yy y yy = () - ¥¥¥ 12 2 1 y = –4y (iii) We have 66pq 2 r 3 = 2 ¥ 3 ¥ 11 ¥ p ¥ q ¥ q ¥ r ¥ r ¥ r and 11qr 2 = 11 ¥ q ¥ r ¥ r \ 66pq 2 r 3 ? 11qr 2 = 66 11 23 2 pq r qr = 23 11 11 ¥ ¥ ¥¥¥ ¥ ¥ ¥ ¥¥ ¥ p q qrrr qr r = 23 1 ¥ ¥¥¥ pq r = 6pqr (iv) We have 34x 3 y 3 z 3 ? 51xy 2 z 3 = 34 51 33 3 23 xy z xy z = 217 317 ¥ ¥ ¥ x x 3 ¥ y y 3 2 ¥ z z 3 3 Page 3 Question: Divide: (i) 24xy 2 z 3 by 6yz 2 (ii) 63a 2 b 4 c 6 by 7a 2 b 2 c 3 Solution: (i) We have 24xy 2 z 3 ? 6yz 2 = 24 6 23 2 xy z yz = 222 3 23 ¥ ¥ ¥ ¥¥ ¥¥ ¥ ¥ ¥¥ ¥¥¥ x yyz zz yz z = 22 1 ¥¥ ¥ ¥ xyz \ 24xy 2 x 3 ? 6yz 2 = 4xyz (ii) 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 63a b c 7a b c 24 6 22 3 = 33 7 7 24 6 22 3 ¥¥ ¥ ¥ ¥ ¥¥ ¥ ab c ab c = 3 ¥ 3 ¥ a a 2 2 ¥ b b 4 2 ¥ c c 6 3 = 9 ¥ a 2–2 ¥ b 4– 2 c 6–3 = 9 ¥ a 0 + b 2 ¥ c 3 = 9 ¥ 1 ¥ b 2 ¥ c 3 = 9b 2 c 3 \ 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 9b 3 c 3 EXERCISE 14.3 Question 1. Carry out the following divisions. (i) 28x 4 ? 56x (ii) –36y 3 ? 9y 2 (iii) 66pq 2 r 3 ? 11qr 2 (iv) 34x 3 y 3 z 3 ? 51xy 2 z 3 (v) 12a 8 b 8 ? (–6a 6 b 4 ) Solution: (i) We have 28x 4 ? 56x = 28 56 4 x x = 227 22 2 7 4 1 ¥¥ ¥ ¥ ¥¥¥ x x = 1 2 ¥ x 4– 1 = 1 2 x 3 \ 28x 4 ? 56x = 1 2 x 3 (ii) We have –36y 3 = (–1) ¥ 2 ¥ 2 ¥ 3 ¥ 3 ¥ y ¥ y ¥ y and 9y 2 = 3 ¥ 3 ¥ y ¥ y \ –36y 3 ? 9y 2 = -36 9 3 2 y y = () - ¥¥¥ ¥ ¥ ¥ ¥ ¥¥ ¥ 12 2 3 3 33 yy y yy = () - ¥¥¥ 12 2 1 y = –4y (iii) We have 66pq 2 r 3 = 2 ¥ 3 ¥ 11 ¥ p ¥ q ¥ q ¥ r ¥ r ¥ r and 11qr 2 = 11 ¥ q ¥ r ¥ r \ 66pq 2 r 3 ? 11qr 2 = 66 11 23 2 pq r qr = 23 11 11 ¥ ¥ ¥¥¥ ¥ ¥ ¥ ¥¥ ¥ p q qrrr qr r = 23 1 ¥ ¥¥¥ pq r = 6pqr (iv) We have 34x 3 y 3 z 3 ? 51xy 2 z 3 = 34 51 33 3 23 xy z xy z = 217 317 ¥ ¥ ¥ x x 3 ¥ y y 3 2 ¥ z z 3 3 = 2 3 ¥ x 3–1 ¥ y 3– 2 ¥ 3z 3–3 = 2 3 ¥ x 2 ¥ y 1 ¥ z 0 = 2 3 ¥ x 2 y ¥ 1 = 2 3 x 2 y (v) We have 12a 8 b 8 ? (–6a 6 b 4 )= 12 6 88 64 ab ab - = 22 3 12 3 88 64 ¥¥ ¥ ¥ -¥ ¥ ¥ ¥ ab ab = 2 1 - ¥ a a 8 6 ¥ b b 8 4 = –2 ¥ a 8– 6 ¥ b 8–4 = –2 ¥ a 2 ¥ b 4 = –2a 2 b 4 Question 2. Divide the given polynomial by the given monomial. (i) (5x 2 – 6x) ? 3x (ii) (3y 8 – 4y 6 + 5y 4 ) ? y 4 (iii) 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 (iv) (x 3 + 2x 2 + 3x) ? 2x (v) (p 3 q 6 – p 6 q 3 ) ? p 3 q 3 Solution: (i) ? (5x 2 – 6x) ? 3x = 5x 6 3 2 - x x = x x () 5x 6 3 - = 5x 6 3 - \ (5x 2 – 6x) ? 3x = 1 3 (5x – 6) (ii) ? (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 34 5y 864 4 yy y -+ = yy y y 44 2 4 34 5 () -+ \ (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 3y 4 – 4y 2 + 5 (iii) ? 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 = 32 2 23 2 2 2 3 22 2 8(xyz xyz xyz) 4xyz ++ = 24 4 22 2 22 2 ¥¥ + + ¥ xy z x y z xy z [] = 2(x y z) 1 ¥+ + = 2(x + y + z) Page 4 Question: Divide: (i) 24xy 2 z 3 by 6yz 2 (ii) 63a 2 b 4 c 6 by 7a 2 b 2 c 3 Solution: (i) We have 24xy 2 z 3 ? 6yz 2 = 24 6 23 2 xy z yz = 222 3 23 ¥ ¥ ¥ ¥¥ ¥¥ ¥ ¥ ¥¥ ¥¥¥ x yyz zz yz z = 22 1 ¥¥ ¥ ¥ xyz \ 24xy 2 x 3 ? 6yz 2 = 4xyz (ii) 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 63a b c 7a b c 24 6 22 3 = 33 7 7 24 6 22 3 ¥¥ ¥ ¥ ¥ ¥¥ ¥ ab c ab c = 3 ¥ 3 ¥ a a 2 2 ¥ b b 4 2 ¥ c c 6 3 = 9 ¥ a 2–2 ¥ b 4– 2 c 6–3 = 9 ¥ a 0 + b 2 ¥ c 3 = 9 ¥ 1 ¥ b 2 ¥ c 3 = 9b 2 c 3 \ 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 9b 3 c 3 EXERCISE 14.3 Question 1. Carry out the following divisions. (i) 28x 4 ? 56x (ii) –36y 3 ? 9y 2 (iii) 66pq 2 r 3 ? 11qr 2 (iv) 34x 3 y 3 z 3 ? 51xy 2 z 3 (v) 12a 8 b 8 ? (–6a 6 b 4 ) Solution: (i) We have 28x 4 ? 56x = 28 56 4 x x = 227 22 2 7 4 1 ¥¥ ¥ ¥ ¥¥¥ x x = 1 2 ¥ x 4– 1 = 1 2 x 3 \ 28x 4 ? 56x = 1 2 x 3 (ii) We have –36y 3 = (–1) ¥ 2 ¥ 2 ¥ 3 ¥ 3 ¥ y ¥ y ¥ y and 9y 2 = 3 ¥ 3 ¥ y ¥ y \ –36y 3 ? 9y 2 = -36 9 3 2 y y = () - ¥¥¥ ¥ ¥ ¥ ¥ ¥¥ ¥ 12 2 3 3 33 yy y yy = () - ¥¥¥ 12 2 1 y = –4y (iii) We have 66pq 2 r 3 = 2 ¥ 3 ¥ 11 ¥ p ¥ q ¥ q ¥ r ¥ r ¥ r and 11qr 2 = 11 ¥ q ¥ r ¥ r \ 66pq 2 r 3 ? 11qr 2 = 66 11 23 2 pq r qr = 23 11 11 ¥ ¥ ¥¥¥ ¥ ¥ ¥ ¥¥ ¥ p q qrrr qr r = 23 1 ¥ ¥¥¥ pq r = 6pqr (iv) We have 34x 3 y 3 z 3 ? 51xy 2 z 3 = 34 51 33 3 23 xy z xy z = 217 317 ¥ ¥ ¥ x x 3 ¥ y y 3 2 ¥ z z 3 3 = 2 3 ¥ x 3–1 ¥ y 3– 2 ¥ 3z 3–3 = 2 3 ¥ x 2 ¥ y 1 ¥ z 0 = 2 3 ¥ x 2 y ¥ 1 = 2 3 x 2 y (v) We have 12a 8 b 8 ? (–6a 6 b 4 )= 12 6 88 64 ab ab - = 22 3 12 3 88 64 ¥¥ ¥ ¥ -¥ ¥ ¥ ¥ ab ab = 2 1 - ¥ a a 8 6 ¥ b b 8 4 = –2 ¥ a 8– 6 ¥ b 8–4 = –2 ¥ a 2 ¥ b 4 = –2a 2 b 4 Question 2. Divide the given polynomial by the given monomial. (i) (5x 2 – 6x) ? 3x (ii) (3y 8 – 4y 6 + 5y 4 ) ? y 4 (iii) 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 (iv) (x 3 + 2x 2 + 3x) ? 2x (v) (p 3 q 6 – p 6 q 3 ) ? p 3 q 3 Solution: (i) ? (5x 2 – 6x) ? 3x = 5x 6 3 2 - x x = x x () 5x 6 3 - = 5x 6 3 - \ (5x 2 – 6x) ? 3x = 1 3 (5x – 6) (ii) ? (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 34 5y 864 4 yy y -+ = yy y y 44 2 4 34 5 () -+ \ (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 3y 4 – 4y 2 + 5 (iii) ? 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 = 32 2 23 2 2 2 3 22 2 8(xyz xyz xyz) 4xyz ++ = 24 4 22 2 22 2 ¥¥ + + ¥ xy z x y z xy z [] = 2(x y z) 1 ¥+ + = 2(x + y + z) \ 8 4 32 2 2 3 2 2 2 3 22 2 () xy x x y z x y z xy z ++ = 2(x + y + z) (iv) ? (x 3 + 2x 2 + 3x) ? 2x = xx x x 32 23 2 ++ = xx x x () 2 23 2 ++ = 1 2 (x 2 + 2x + 3) \ (x 3 + 2x 2 + 3x) ? 2x = 1 2 (x 2 + 2x + 3) (v) ? (P 3 q 6 – p 6 q 3 ) ? p 3 q 3 = pq p q pq 36 6 3 33 - = pq q p pq 33 3 3 33 [] - = qp 1 33 - \ (p 3 q 6 – p 6 q 3 ) ? p 3 q 3 = q 3 – p 3 Question 3. Work out the following divisions: (i) (10x – 25) ? 5 (ii) (10x – 25) ? (2x – 5) (iii) 10y(6y + 21) ? 5(2y + 7) (iv) 9x 2 y 2 (3z – 24) ? 27xy(z – 8) (v) 96abc(3a – 12)(5b – 30) ? 144(a – 4)(b – 6) Solution: (i) ? 10x – 25 = 5(2x – 5) \ 10 25 5 x - = 52 5 5 () x - = (2x – 5) Thus, (10x – 25) ? 5 = 2x – 5 (ii) ? 10x – 25 = 5(2x – 5) \ 10 25 25 x x - - = 52 5 25 () () x x - - = 5 Thus, (10x – 25) ? (2x – 5) = 5 (iii) ? 6y + 21 = 3(2y + 7) \ 10 6 21 52 7 yy y () () + + = 10 3 2 7 52 7 yy y ¥¥ + + () () = 2 ¥ y ¥ 3 = 6y \ 10y(6y + 21) ? 5(2y + 7) = 6y (iv) ? 3z – 24 = 3(z – 8) \ 93 24 27 8 22 xy z xy z () () - - = 22 33 x y 3 (z 8) 33 3 x y (z 8) ´´ ´ ´´ - ´´ ´ ´ ´ - Page 5 Question: Divide: (i) 24xy 2 z 3 by 6yz 2 (ii) 63a 2 b 4 c 6 by 7a 2 b 2 c 3 Solution: (i) We have 24xy 2 z 3 ? 6yz 2 = 24 6 23 2 xy z yz = 222 3 23 ¥ ¥ ¥ ¥¥ ¥¥ ¥ ¥ ¥¥ ¥¥¥ x yyz zz yz z = 22 1 ¥¥ ¥ ¥ xyz \ 24xy 2 x 3 ? 6yz 2 = 4xyz (ii) 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 63a b c 7a b c 24 6 22 3 = 33 7 7 24 6 22 3 ¥¥ ¥ ¥ ¥ ¥¥ ¥ ab c ab c = 3 ¥ 3 ¥ a a 2 2 ¥ b b 4 2 ¥ c c 6 3 = 9 ¥ a 2–2 ¥ b 4– 2 c 6–3 = 9 ¥ a 0 + b 2 ¥ c 3 = 9 ¥ 1 ¥ b 2 ¥ c 3 = 9b 2 c 3 \ 63a 2 b 4 c 6 ? 7a 2 b 2 c 3 = 9b 3 c 3 EXERCISE 14.3 Question 1. Carry out the following divisions. (i) 28x 4 ? 56x (ii) –36y 3 ? 9y 2 (iii) 66pq 2 r 3 ? 11qr 2 (iv) 34x 3 y 3 z 3 ? 51xy 2 z 3 (v) 12a 8 b 8 ? (–6a 6 b 4 ) Solution: (i) We have 28x 4 ? 56x = 28 56 4 x x = 227 22 2 7 4 1 ¥¥ ¥ ¥ ¥¥¥ x x = 1 2 ¥ x 4– 1 = 1 2 x 3 \ 28x 4 ? 56x = 1 2 x 3 (ii) We have –36y 3 = (–1) ¥ 2 ¥ 2 ¥ 3 ¥ 3 ¥ y ¥ y ¥ y and 9y 2 = 3 ¥ 3 ¥ y ¥ y \ –36y 3 ? 9y 2 = -36 9 3 2 y y = () - ¥¥¥ ¥ ¥ ¥ ¥ ¥¥ ¥ 12 2 3 3 33 yy y yy = () - ¥¥¥ 12 2 1 y = –4y (iii) We have 66pq 2 r 3 = 2 ¥ 3 ¥ 11 ¥ p ¥ q ¥ q ¥ r ¥ r ¥ r and 11qr 2 = 11 ¥ q ¥ r ¥ r \ 66pq 2 r 3 ? 11qr 2 = 66 11 23 2 pq r qr = 23 11 11 ¥ ¥ ¥¥¥ ¥ ¥ ¥ ¥¥ ¥ p q qrrr qr r = 23 1 ¥ ¥¥¥ pq r = 6pqr (iv) We have 34x 3 y 3 z 3 ? 51xy 2 z 3 = 34 51 33 3 23 xy z xy z = 217 317 ¥ ¥ ¥ x x 3 ¥ y y 3 2 ¥ z z 3 3 = 2 3 ¥ x 3–1 ¥ y 3– 2 ¥ 3z 3–3 = 2 3 ¥ x 2 ¥ y 1 ¥ z 0 = 2 3 ¥ x 2 y ¥ 1 = 2 3 x 2 y (v) We have 12a 8 b 8 ? (–6a 6 b 4 )= 12 6 88 64 ab ab - = 22 3 12 3 88 64 ¥¥ ¥ ¥ -¥ ¥ ¥ ¥ ab ab = 2 1 - ¥ a a 8 6 ¥ b b 8 4 = –2 ¥ a 8– 6 ¥ b 8–4 = –2 ¥ a 2 ¥ b 4 = –2a 2 b 4 Question 2. Divide the given polynomial by the given monomial. (i) (5x 2 – 6x) ? 3x (ii) (3y 8 – 4y 6 + 5y 4 ) ? y 4 (iii) 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 (iv) (x 3 + 2x 2 + 3x) ? 2x (v) (p 3 q 6 – p 6 q 3 ) ? p 3 q 3 Solution: (i) ? (5x 2 – 6x) ? 3x = 5x 6 3 2 - x x = x x () 5x 6 3 - = 5x 6 3 - \ (5x 2 – 6x) ? 3x = 1 3 (5x – 6) (ii) ? (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 34 5y 864 4 yy y -+ = yy y y 44 2 4 34 5 () -+ \ (3y 8 – 4y 6 + 5y 4 ) ? y 4 = 3y 4 – 4y 2 + 5 (iii) ? 8(x 3 y 2 z 2 + x 2 y 3 z 2 + x 2 y 2 z 3 ) ? 4x 2 y 2 z 2 = 32 2 23 2 2 2 3 22 2 8(xyz xyz xyz) 4xyz ++ = 24 4 22 2 22 2 ¥¥ + + ¥ xy z x y z xy z [] = 2(x y z) 1 ¥+ + = 2(x + y + z) \ 8 4 32 2 2 3 2 2 2 3 22 2 () xy x x y z x y z xy z ++ = 2(x + y + z) (iv) ? (x 3 + 2x 2 + 3x) ? 2x = xx x x 32 23 2 ++ = xx x x () 2 23 2 ++ = 1 2 (x 2 + 2x + 3) \ (x 3 + 2x 2 + 3x) ? 2x = 1 2 (x 2 + 2x + 3) (v) ? (P 3 q 6 – p 6 q 3 ) ? p 3 q 3 = pq p q pq 36 6 3 33 - = pq q p pq 33 3 3 33 [] - = qp 1 33 - \ (p 3 q 6 – p 6 q 3 ) ? p 3 q 3 = q 3 – p 3 Question 3. Work out the following divisions: (i) (10x – 25) ? 5 (ii) (10x – 25) ? (2x – 5) (iii) 10y(6y + 21) ? 5(2y + 7) (iv) 9x 2 y 2 (3z – 24) ? 27xy(z – 8) (v) 96abc(3a – 12)(5b – 30) ? 144(a – 4)(b – 6) Solution: (i) ? 10x – 25 = 5(2x – 5) \ 10 25 5 x - = 52 5 5 () x - = (2x – 5) Thus, (10x – 25) ? 5 = 2x – 5 (ii) ? 10x – 25 = 5(2x – 5) \ 10 25 25 x x - - = 52 5 25 () () x x - - = 5 Thus, (10x – 25) ? (2x – 5) = 5 (iii) ? 6y + 21 = 3(2y + 7) \ 10 6 21 52 7 yy y () () + + = 10 3 2 7 52 7 yy y ¥¥ + + () () = 2 ¥ y ¥ 3 = 6y \ 10y(6y + 21) ? 5(2y + 7) = 6y (iv) ? 3z – 24 = 3(z – 8) \ 93 24 27 8 22 xy z xy z () () - - = 22 33 x y 3 (z 8) 33 3 x y (z 8) ´´ ´ ´´ - ´´ ´ ´ ´ - = x x 2 ¥ y y 2 = x 2–1 y 2–1 = xy \ 9x 2 y 2 (3z – 24) ? 27xy(z – 8) = xy (v) ? 3a – 12 = 3(a – 4) 5b – 30 = 5(b – 6) 96 = 2 ¥ 2 ¥ 2 ¥ 2 ¥ 2 ¥ 3 and 144 = 2 ¥ 2 ¥ 2 ¥ 2 ¥ 3 ¥ 3 \ 96 3 12 5 30 144( 4 6 abc a b ab ()( ) )( ) -- -- = 2222 2 3 3 4 5 6 2 2 223 3 4 6 ¥ ¥¥¥¥ ¥ ¥ ¥ ¥ ¥ - ¥ ¥ - ¥¥¥¥ ¥ ¥ - ¥ - ab c a b ab () ( ) ()( ) = 2 ¥ 5 ¥ a ¥ b ¥ c = 10abc Thus, 96abc (3a – 12)(5b – 36) ? 144(a – 4)(b – 6) = 10abc Question 4. Divide as directed. (i) 5(2x + 1)(3x + 5) ? (2x + 1) (ii) 26xy(x + 5)(y – 4) ? 13x(y – 4) (iii) 52pqr(p + q)(q + r)(r + p) ? 104pq(q + r)(r + p) (iv) 20(y + 4)(y 2 + 5y + 3) ? 5(y + 4) (v) x(x + 1)(x + 2) (x + 3) ? x(x + 1) Solution: (i) We have 5(2x + 1)(3x + 5) ? (2x + 1) = 52 1 3 5 21 ()( ) () xx x ++ + = 53 5 1 ¥+ () x = 5(3x + 5) \ 5(2x + 1)(3x + 5) ? (2x + 1) = 5(3x + 5) (ii) We have 26xy(x + 5)(y – 4) ? 13x(y – 4)= 26 5 4 13 4 xy x y xy ()( ) () +- - = 2y(x 5) 1 ¥+ \ 26xy(x + 5)(y – 4) ? 13x(y – 4) = 2y(x + 5) (iii) We have 52pqr (p q) (q r) (r p) 104pq (q r) (r p) ++ + ++ = 52 252 ¥¥ ¥ ¥ + + + ¥¥ ¥ + + pq r p q q r r p pqq r r p ()( )( ) ()( ) = rq r ¥+ () 2 \ 52pqr(p + q)(q + r)(r +p) ? 104pq(q + r)(r + p) = 1 2 r(p q) +Read More
90 docs|16 tests
|
1. What is factorisation in mathematics? |
2. Why is factorisation important in mathematics? |
3. How do you factorise a quadratic expression? |
4. What are the methods of factorisation? |
5. How is factorisation used in real-life situations? |
|
Explore Courses for Class 8 exam
|