Question

(c) a² - 6² (d) (a-b) (a+b) (c)-12 (d) 12 (c)x+99 (d) xyz (b) a+62 (c) a?+62+ 2ab (d) a +b-2ab - - - - (b) a? - b2 + 2ab 38. Using identity a? - b? =(a+b) (a-b), find 42 - 6 : (a) -20 (b) 20 39. The expression in one variable is: (a) x+x+1 (b)x+y 40. (a+b)(a-b) is equal to: (a) a?. ? 41. The product of (z-1)(z-8); (a) z² - 8z + 8 (b) z2 - 7z+8 42. Expand (4a - 3b - 3 c)? (a) 16 a 2-362-4c2 + 24ab- 12bc - 16ac ) (c) 16 a 2 +962 + 4c? + 12ab - 12bc - 24ca 43. Factor of 3x2 + 3y + 7 + 6xy + 213 yz + 2V3 xz: (a) (3x + 3y + z)? 44. When (1 - 8a) is divided by (1 – 2a), the quotient is: (b) (13x + V3y + z)? (©) (3x+y + V3z)(d) (13x – V3y + z)? ?- (a) 1 + 2a - 4a? (b) (1 - 2a) 45. Find the value of a? -b' if a - b = 5 and ab =-2: (a) 105 (b) 65 (d) none 46. If a + b +c=0 then a² 6² c² + + bc ac ab (c) 7 - 9z+8 (d) none of these (b) 16 a 2 +962 +4c2-24bc -16ac . (d) None of these - - - (C) 1 + 2a + 4a? - - (d) 1 - 2a + 4a? = (C) 104 ALIG* SURE SUCCESS Page 58​

Answer 1

Answer:

(a+b+c)

2

=a

2

+b

2

+c

2

+2(ab+bc+ca)

9

2

=35+2(ab+bc+ca)

2(ab+bc+ca)=81−35=46

(ab+bc+ca)=23

using formula,

(a

3

+b

3

+c

3

)−3abc=(a

2

+b

2

+c

2

−ab−bc−ca)(a+b+c)

a

3

+b

3

+c

3

−3abc=(35−23)×9=9×12=108