(Mathematics-Part-2) NDA/NA Solved Paper 2017-I

Total Questions: 50

21. Solve the following equation:

Correct Answer: (b) 1/2
Solution:

22. Solve the following equation:

Correct Answer: (b) 1
Solution:

23. Solve the following equation:


Correct Answer: (d)
Solution:

24. The function f: X→Y defined by f(x) = cos x, where x ∈ X, is one-one and on to if X and Y are respectively equal to

Correct Answer: (a)
Solution:

Observe the cosx graph in the figure.
It is clear that, function is one - one and onto when x and y are [o, π] and [-1, 1]

25. Solve the following equation:


Correct Answer: (b)
Solution:

26. Solve the following equation:


Correct Answer: (d)
Solution:

27. Let f:[-6, 6] → R be defined by f (x) =x² - 3. Consider the following:

1. (f°f°S)(-1) = (f°f°f) (1)
2. (f°f°f) (-1) -4 (f°f°f) (1) = (f°f) (0)
Which of the above is/are correct?

Correct Answer: (c) Both I and 2
Solution:

28. Let f(x)=px + q and g(x)=mx + n. Then f (g(x)) =g(f (x)) is equivalent to

Correct Answer: (c) f (n) = g (q)
Solution:

29. Solve the following equation:


Correct Answer: (c)
Solution:

30. What is dx²/dy² equal to?

Correct Answer: (c)
Solution: