Algebra (Railway Maths) (Part – VII)

Total Questions: 50

11. Find the answer of given question? [RRB NTPC 23/01/2021 (Morning) ]

Correct Answer: (b) 1/2
Solution:

12. Find the value of a² + b² + c² − 2ab + 2ac − 2bc, if a = x + y, b = x − y and c = 2x − 1 [RRB NTPC 25/01/2021 (Morning)]

Correct Answer: (b) (2x + 2y − 1)²
Solution:

13. If (√7 + √2) / (√7 − √2) = x + y√14, find the value of y. [RRB NTPC 25/01/2021 (Morning)]

Correct Answer: (d) 2/5
Solution:

14. If x = (√3 + 1) / (√3 − 1) and y = (√3 − 1) / (√3 + 1), then find the value of x² + y². [RRB NTPC 27/01/2021 (Evening)]

Correct Answer: (c) 14
Solution:

15. If (3√2 − 2√3) / (3√2 + 2√3) = a + b√6, then find the value of b. [RRB NTPC 27/01/2021 (Evening)]

Correct Answer: (d) −2
Solution:

16. If x² = y + z, y² = z + x and z² = x + y, then find the value of 1/(x + 1) + 1/(y + 1) + 1/(z + 1) [RRB NTPC 28/01/2021 (Morning)]

Correct Answer: (d) 1
Solution:

17. If (3√5 − 5) / (3√5 + 5) = a + b√5, then find the value of b. [RRB NTPC 28/01/2021 (Morning)]

Correct Answer: (d) −3/2
Solution:

18. If x⁴ + 1/x⁴ = 322 and x > 1, then what is the value of x³ − 1/x³? [RRB NTPC 28/01/2021 (Evening)]

Correct Answer: (c) 76
Solution:

19. If √(x/144) = 27/12, find the value of x [RRB NTPC 28/01/2021 (Evening)]

Correct Answer: (d) 729
Solution:

20. If x + 1/x = 5, then the value of 3x / (2x² + 2 − 5x) will be: [RRB NTPC 29/01/2021 (Morning)]

Correct Answer: (b) 3/5
Solution: