Algebra (Railway Maths) (Part – VIII)

Total Questions: 50

31. IF a - b = 4 and a² + b² = 10 then the value of a³ - b³ is: [RRB NTPC 03/03/2021 (Evening) ]

Correct Answer: (d) 28
Solution:

32. If 2a = 3b = 4c and a + b + c = 13 √2, then a² + b² + c² is: [RRB NTPC 04/03/2021 (Morning) ]

Correct Answer: (d) 122
Solution:

33. If x⁴ + 1/x⁴ = 322 and x>1, then what is the value of x - 1/x? [RRB NTPC 04/03/2021 (Morning) ]

Correct Answer: (c) 4
Solution:

34. For x > 0 find the value of (1 + 1/x + 1) (1 + 1/x + 2) (1 + 1/x + 3) (1 + 1/x + 4) [RRB NTPC 04/03/2021 (Evening) ]

Correct Answer: (d) x + 5 / x + 1
Solution:

35. If (a + b + c) = 6, a² + b² + c² = 2, [RRB NTPC 04/03/2021 (Evening) ]

Correct Answer: (c) 17
Solution:

36. If (√2 + 1)³ = a + b√2, then the correct relation between a and b is [RRB NTPC 05/03/2021 (Morning) ]

Correct Answer: (a) a - b = 2
Solution:

37. If 2ˣ = 4ʸ ⁺ ¹ and 3ʸ = 3ˣ ⁻ ⁹, then the values of x and y, respectively, are: [RRB NTPC 07/03/2021 (Evening) ]

Correct Answer: (a) 16 ,7
Solution:

38. If x² + 25y² = 10xy, then x : y = ? [RRB NTPC 08/03/2021 (Evening) ]

Correct Answer: (c) 5 : 1
Solution:

39. If x + y = 9 and xy = 18, then the value of x² + y² is: [RRB NTPC 08/03/2021 (Evening) ]

Correct Answer: (d) 45
Solution:

40. If x = 2 + √5, then the value of (x - 1/3)³ is: [RRB NTPC 08/03/2021 (Evening) ]

Correct Answer: (b) 64
Solution: