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Page 1 re Page 2 re (-6a + 6b + c -4) S o l u t i o n : c (-6a + 17b) 6a +4b -c +3 +2b -3c +4 -7a +11b +2c -1 -5a +2c -6 ¯ -6a +17b + 0c +0 Q u e s t i o n : 7 8 Tick ? the correct answer: (3q + 7p 2 - 2r 3 + 4) - (4p 2 - 2q + 7r 3 - 3) = ? a (p 2 + 2q + 5r 3 + 1) b (11p 2 + q + 5r 3 + 1) c (-3p 2 - 5q + 9r 3 - 7) d (3p 2 + 5q - 9r 3 +7) S o l u t i o n : d (3p 2 + 5q - 9r 3 +7) 7p 2 +3q -2r 3 +4 4p 2 -2q +7r 3 -3 - + - + ¯ 3p 2 + 5q -9r 3 + 7 Q u e s t i o n : 7 9 Tick ? the correct answer: (x + 5)x -3 = ? a x 2 + 5x - 15 b x 2 - 3x - 15 c x 2 + 2x + 15 d x 2 + 2x - 15 S o l u t i o n : d x 2 + 2x - 15 (x +5)(x -3) ? (x)(x -3)+(5)(x -3) ? x 2 -3x +5x -15 ? x 2 +2x -15 Q u e s t i o n : 8 0 Tick ? the correct answer: (2x + 3)(3x - 1) = ? a (6x 2 + 8x - 3) b (6x 2 + 7x - 3) c 6x 2 - 7x - 3 d (6x 2 - 7x + 3) S o l u t i o n : b (6x 2 + 7x - 3) (2x +3)(3x -1) ? (2x)(3x -1)+(3)(3x -1) ? 6x 2 -2x +9x -3 ? 6x 2 +7x -3 Q u e s t i o n : 8 1 Tick ? the correct answer: (x + 4)(x + 4) = ? a (x 2 + 16) b (x 2 + 4x + 16) c (x 2 + 8x + 16) d (x 2 + 16x) S o l u t i o n : c (x 2 + 8x + 16) (x +4)(x +4) ? (x +4) 2 according to the formula (a +b) 2 = a 2 +2ab +b 2 ? x 2 +2(x)(4)+(4) 2 ? x 2 +8x +16 Q u e s t i o n : 8 2 Tick ( ) ( ) Page 3 re (-6a + 6b + c -4) S o l u t i o n : c (-6a + 17b) 6a +4b -c +3 +2b -3c +4 -7a +11b +2c -1 -5a +2c -6 ¯ -6a +17b + 0c +0 Q u e s t i o n : 7 8 Tick ? the correct answer: (3q + 7p 2 - 2r 3 + 4) - (4p 2 - 2q + 7r 3 - 3) = ? a (p 2 + 2q + 5r 3 + 1) b (11p 2 + q + 5r 3 + 1) c (-3p 2 - 5q + 9r 3 - 7) d (3p 2 + 5q - 9r 3 +7) S o l u t i o n : d (3p 2 + 5q - 9r 3 +7) 7p 2 +3q -2r 3 +4 4p 2 -2q +7r 3 -3 - + - + ¯ 3p 2 + 5q -9r 3 + 7 Q u e s t i o n : 7 9 Tick ? the correct answer: (x + 5)x -3 = ? a x 2 + 5x - 15 b x 2 - 3x - 15 c x 2 + 2x + 15 d x 2 + 2x - 15 S o l u t i o n : d x 2 + 2x - 15 (x +5)(x -3) ? (x)(x -3)+(5)(x -3) ? x 2 -3x +5x -15 ? x 2 +2x -15 Q u e s t i o n : 8 0 Tick ? the correct answer: (2x + 3)(3x - 1) = ? a (6x 2 + 8x - 3) b (6x 2 + 7x - 3) c 6x 2 - 7x - 3 d (6x 2 - 7x + 3) S o l u t i o n : b (6x 2 + 7x - 3) (2x +3)(3x -1) ? (2x)(3x -1)+(3)(3x -1) ? 6x 2 -2x +9x -3 ? 6x 2 +7x -3 Q u e s t i o n : 8 1 Tick ? the correct answer: (x + 4)(x + 4) = ? a (x 2 + 16) b (x 2 + 4x + 16) c (x 2 + 8x + 16) d (x 2 + 16x) S o l u t i o n : c (x 2 + 8x + 16) (x +4)(x +4) ? (x +4) 2 according to the formula (a +b) 2 = a 2 +2ab +b 2 ? x 2 +2(x)(4)+(4) 2 ? x 2 +8x +16 Q u e s t i o n : 8 2 Tick ( ) ( ) ? the correct answer: (x - 6)(x - 6) = ? a (x 2 - 36) b (x 2 + 36) c (x 2 - 6x + 36) d (x 2 - 12x + 36) S o l u t i o n : d (x 2 - 12x + 36) (x -6)(x -6) ? (x -6) 2 according to the formula (a -b) 2 = a 2 -2ab +b 2 ? x 2 -2(x)(6)+(6) 2 ? x 2 -12x +36 Q u e s t i o n : 8 3 Tick ? the correct answer: (2x + 5)(2x - 5) = ? a (4x 2 + 25) b (4x 2 - 25) c (4x 2 - 10x + 25) d (4x 2 + 10x - 25) S o l u t i o n : b (4x 2 - 25) (2x +5)(2x -5) ? (2x) 2 -(5) 2 according to the formula (a +b)(a -b) = a 2 -b 2 ? 4x 2 - 25 Q u e s t i o n : 8 4 Tick ? the correct answer: 8a 2 b 3 ÷ (-2ab) = ? a 4ab 2 b 4a 2 b c -4ab 2 d -4a 2 b S o l u t i o n : c -4ab 2 8a 2 b 3 ÷ (-2ab) ? 8 -2 a 2-1 b 3-1 ? -4ab 2 Q u e s t i o n : 8 5 Tick ? the correct answer: (2x 2 + 3x + 1) ÷ (x + 1) = ? a (x + 1) b (2x + 1) c (x + 3) d (2x + 3) S o l u t i o n : b (2x + 1) Q u e s t i o n : 8 6 Tick ? the correct answer: (x 2 - 4x + 4) ÷ (x - 2) = ? a (x - 2) ( ) ( ) ( ) ( ) ( ) ( ) Page 4 re (-6a + 6b + c -4) S o l u t i o n : c (-6a + 17b) 6a +4b -c +3 +2b -3c +4 -7a +11b +2c -1 -5a +2c -6 ¯ -6a +17b + 0c +0 Q u e s t i o n : 7 8 Tick ? the correct answer: (3q + 7p 2 - 2r 3 + 4) - (4p 2 - 2q + 7r 3 - 3) = ? a (p 2 + 2q + 5r 3 + 1) b (11p 2 + q + 5r 3 + 1) c (-3p 2 - 5q + 9r 3 - 7) d (3p 2 + 5q - 9r 3 +7) S o l u t i o n : d (3p 2 + 5q - 9r 3 +7) 7p 2 +3q -2r 3 +4 4p 2 -2q +7r 3 -3 - + - + ¯ 3p 2 + 5q -9r 3 + 7 Q u e s t i o n : 7 9 Tick ? the correct answer: (x + 5)x -3 = ? a x 2 + 5x - 15 b x 2 - 3x - 15 c x 2 + 2x + 15 d x 2 + 2x - 15 S o l u t i o n : d x 2 + 2x - 15 (x +5)(x -3) ? (x)(x -3)+(5)(x -3) ? x 2 -3x +5x -15 ? x 2 +2x -15 Q u e s t i o n : 8 0 Tick ? the correct answer: (2x + 3)(3x - 1) = ? a (6x 2 + 8x - 3) b (6x 2 + 7x - 3) c 6x 2 - 7x - 3 d (6x 2 - 7x + 3) S o l u t i o n : b (6x 2 + 7x - 3) (2x +3)(3x -1) ? (2x)(3x -1)+(3)(3x -1) ? 6x 2 -2x +9x -3 ? 6x 2 +7x -3 Q u e s t i o n : 8 1 Tick ? the correct answer: (x + 4)(x + 4) = ? a (x 2 + 16) b (x 2 + 4x + 16) c (x 2 + 8x + 16) d (x 2 + 16x) S o l u t i o n : c (x 2 + 8x + 16) (x +4)(x +4) ? (x +4) 2 according to the formula (a +b) 2 = a 2 +2ab +b 2 ? x 2 +2(x)(4)+(4) 2 ? x 2 +8x +16 Q u e s t i o n : 8 2 Tick ( ) ( ) ? the correct answer: (x - 6)(x - 6) = ? a (x 2 - 36) b (x 2 + 36) c (x 2 - 6x + 36) d (x 2 - 12x + 36) S o l u t i o n : d (x 2 - 12x + 36) (x -6)(x -6) ? (x -6) 2 according to the formula (a -b) 2 = a 2 -2ab +b 2 ? x 2 -2(x)(6)+(6) 2 ? x 2 -12x +36 Q u e s t i o n : 8 3 Tick ? the correct answer: (2x + 5)(2x - 5) = ? a (4x 2 + 25) b (4x 2 - 25) c (4x 2 - 10x + 25) d (4x 2 + 10x - 25) S o l u t i o n : b (4x 2 - 25) (2x +5)(2x -5) ? (2x) 2 -(5) 2 according to the formula (a +b)(a -b) = a 2 -b 2 ? 4x 2 - 25 Q u e s t i o n : 8 4 Tick ? the correct answer: 8a 2 b 3 ÷ (-2ab) = ? a 4ab 2 b 4a 2 b c -4ab 2 d -4a 2 b S o l u t i o n : c -4ab 2 8a 2 b 3 ÷ (-2ab) ? 8 -2 a 2-1 b 3-1 ? -4ab 2 Q u e s t i o n : 8 5 Tick ? the correct answer: (2x 2 + 3x + 1) ÷ (x + 1) = ? a (x + 1) b (2x + 1) c (x + 3) d (2x + 3) S o l u t i o n : b (2x + 1) Q u e s t i o n : 8 6 Tick ? the correct answer: (x 2 - 4x + 4) ÷ (x - 2) = ? a (x - 2) ( ) ( ) ( ) ( ) ( ) ( ) b (x + 2) c (2 - x) d (2 + x + x 2 ) S o l u t i o n : a (x - 2) Q u e s t i o n : 8 7 Tick ? the correct answer: (a + 1)(a - 1)(a 2 + 1) = ? a (a 4 - 2a 2 - 1) b (a 4 - a 2 - 1) c (a 4 - 1) d (a 4 + 1) S o l u t i o n : c (a 4 - 1) (i) (a +1)(a -1) a 2 +1 ? (a) 2 -(1) 2 a 2 +1 according to the formula a 2 -b 2 = (a +b)(a -b) ? a 2 -1 a 2 +1 ? a 2 2 - 1 2 2 according to the formula a 2 -b 2 = (a +b)(a -b) ? Q u e s t i o n : 8 8 Tick ? the correct answer: 1 x + 1 y 1 x - 1 y = ? a 1 x 2 - 1 y 2 b 1 x 2 + 1 y 2 c 1 x 2 + 1 y 2 - 1 xy d 1 x 2 - 1 y 2 + 1 xy S o l u t i o n : a) ( 1 x 2 - 1 y 2 ) ( 1 x + 1 y )( 1 ( ) ( ) ( ) [ ] ( ) ( ) ( ) ( ) [ ] ( ) ( ) ( ) ( ) ( ) ( ) Page 5 re (-6a + 6b + c -4) S o l u t i o n : c (-6a + 17b) 6a +4b -c +3 +2b -3c +4 -7a +11b +2c -1 -5a +2c -6 ¯ -6a +17b + 0c +0 Q u e s t i o n : 7 8 Tick ? the correct answer: (3q + 7p 2 - 2r 3 + 4) - (4p 2 - 2q + 7r 3 - 3) = ? a (p 2 + 2q + 5r 3 + 1) b (11p 2 + q + 5r 3 + 1) c (-3p 2 - 5q + 9r 3 - 7) d (3p 2 + 5q - 9r 3 +7) S o l u t i o n : d (3p 2 + 5q - 9r 3 +7) 7p 2 +3q -2r 3 +4 4p 2 -2q +7r 3 -3 - + - + ¯ 3p 2 + 5q -9r 3 + 7 Q u e s t i o n : 7 9 Tick ? the correct answer: (x + 5)x -3 = ? a x 2 + 5x - 15 b x 2 - 3x - 15 c x 2 + 2x + 15 d x 2 + 2x - 15 S o l u t i o n : d x 2 + 2x - 15 (x +5)(x -3) ? (x)(x -3)+(5)(x -3) ? x 2 -3x +5x -15 ? x 2 +2x -15 Q u e s t i o n : 8 0 Tick ? the correct answer: (2x + 3)(3x - 1) = ? a (6x 2 + 8x - 3) b (6x 2 + 7x - 3) c 6x 2 - 7x - 3 d (6x 2 - 7x + 3) S o l u t i o n : b (6x 2 + 7x - 3) (2x +3)(3x -1) ? (2x)(3x -1)+(3)(3x -1) ? 6x 2 -2x +9x -3 ? 6x 2 +7x -3 Q u e s t i o n : 8 1 Tick ? the correct answer: (x + 4)(x + 4) = ? a (x 2 + 16) b (x 2 + 4x + 16) c (x 2 + 8x + 16) d (x 2 + 16x) S o l u t i o n : c (x 2 + 8x + 16) (x +4)(x +4) ? (x +4) 2 according to the formula (a +b) 2 = a 2 +2ab +b 2 ? x 2 +2(x)(4)+(4) 2 ? x 2 +8x +16 Q u e s t i o n : 8 2 Tick ( ) ( ) ? the correct answer: (x - 6)(x - 6) = ? a (x 2 - 36) b (x 2 + 36) c (x 2 - 6x + 36) d (x 2 - 12x + 36) S o l u t i o n : d (x 2 - 12x + 36) (x -6)(x -6) ? (x -6) 2 according to the formula (a -b) 2 = a 2 -2ab +b 2 ? x 2 -2(x)(6)+(6) 2 ? x 2 -12x +36 Q u e s t i o n : 8 3 Tick ? the correct answer: (2x + 5)(2x - 5) = ? a (4x 2 + 25) b (4x 2 - 25) c (4x 2 - 10x + 25) d (4x 2 + 10x - 25) S o l u t i o n : b (4x 2 - 25) (2x +5)(2x -5) ? (2x) 2 -(5) 2 according to the formula (a +b)(a -b) = a 2 -b 2 ? 4x 2 - 25 Q u e s t i o n : 8 4 Tick ? the correct answer: 8a 2 b 3 ÷ (-2ab) = ? a 4ab 2 b 4a 2 b c -4ab 2 d -4a 2 b S o l u t i o n : c -4ab 2 8a 2 b 3 ÷ (-2ab) ? 8 -2 a 2-1 b 3-1 ? -4ab 2 Q u e s t i o n : 8 5 Tick ? the correct answer: (2x 2 + 3x + 1) ÷ (x + 1) = ? a (x + 1) b (2x + 1) c (x + 3) d (2x + 3) S o l u t i o n : b (2x + 1) Q u e s t i o n : 8 6 Tick ? the correct answer: (x 2 - 4x + 4) ÷ (x - 2) = ? a (x - 2) ( ) ( ) ( ) ( ) ( ) ( ) b (x + 2) c (2 - x) d (2 + x + x 2 ) S o l u t i o n : a (x - 2) Q u e s t i o n : 8 7 Tick ? the correct answer: (a + 1)(a - 1)(a 2 + 1) = ? a (a 4 - 2a 2 - 1) b (a 4 - a 2 - 1) c (a 4 - 1) d (a 4 + 1) S o l u t i o n : c (a 4 - 1) (i) (a +1)(a -1) a 2 +1 ? (a) 2 -(1) 2 a 2 +1 according to the formula a 2 -b 2 = (a +b)(a -b) ? a 2 -1 a 2 +1 ? a 2 2 - 1 2 2 according to the formula a 2 -b 2 = (a +b)(a -b) ? Q u e s t i o n : 8 8 Tick ? the correct answer: 1 x + 1 y 1 x - 1 y = ? a 1 x 2 - 1 y 2 b 1 x 2 + 1 y 2 c 1 x 2 + 1 y 2 - 1 xy d 1 x 2 - 1 y 2 + 1 xy S o l u t i o n : a) ( 1 x 2 - 1 y 2 ) ( 1 x + 1 y )( 1 ( ) ( ) ( ) [ ] ( ) ( ) ( ) ( ) [ ] ( ) ( ) ( ) ( ) ( ) ( ) x - 1 y ) ? According to the formula (a +b)(a -b) = (a) 2 -(b) 2 : ? ( 1 x 2 - 1 y 2 ) Q u e s t i o n : 8 9 Tick ? the correct answer: If x + 1 x = 5 , then x 2 + 1 x 2 = ? a 25 b 27 c 23 d 25 1 25 S o l u t i o n : c 23 x + 1 x = 5 ? Squaring both the sides: ? x + 1 x 2 = (5) 2 ? x 2 + 1 x 2 +2(x) 1 x = 25 ? x 2 + 1 x 2 +2 = 25 ? x 2 + 1 x 2 = 25 -2 ? x 2 + 1 x 2 = 23 Q u e s t i o n : 9 0 Tick ? the correct answer: If x - 1 x = 6 , then x 2 + 1 x 2 = ? a 36 b 38 c 32 d 36 1 36 S o l u t i o n : b 38 x - 1 x = 6 ? Squaring both the sides: ? x - 1 x 2 = (6) 2 ? x 2 + 1 x 2 -2(x) 1 x = 36 ? x 2 + 1 x 2 -2 = 36 ? x 2 + 1 x 2 = 36 +2 ? x 2 + 1 x 2 = 38 Q u e s t i o n : 9 1 Tick ? the correct answer: 82 2 - 18 2 = ? a 8218 b 6418 c 6400 d 7204 S o l u t i o n : c 6400 (82) 2 -(18) 2 = (82 + 18)(82 - 18) = (100)(64) = 6400 [using the identity ( - ) ( ) ( ) ( ) ( ) ( ( ) ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ( ) ) ( ) ( ) ( )Read More
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