NIMCET 2011 — Mathematics PYQ
NIMCET | Mathematics | 2011limx→∞(x−cosx)(x+sinx) is equal to:
Choose the correct answer:
- A.
0
- B.
1
(Correct Answer) - C.
-1
- D.
None of these
1
Explanation
Step 1: Write the limit expression
Let the limit be L:
Step 2: Divide numerator and denominator by x
Inside the square root, we divide every term by x:
Step 3: Apply the limit x→∞
We know that both sinx and cosx are bounded functions, meaning their values always stay between −1 and 1.
As x approaches infinity, any finite value divided by an infinitely large number tends to zero:
Step 4: Calculate the final value
Substitute these zeros back into the expression:
Conclusion:
The value of the limit is 1.
Correct Option:
(b) 1
Explanation
Step 1: Write the limit expression
Let the limit be L:
Step 2: Divide numerator and denominator by x
Inside the square root, we divide every term by x:
Step 3: Apply the limit x→∞
We know that both sinx and cosx are bounded functions, meaning their values always stay between −1 and 1.
As x approaches infinity, any finite value divided by an infinitely large number tends to zero:
Step 4: Calculate the final value
Substitute these zeros back into the expression:
Conclusion:
The value of the limit is 1.
Correct Option:
(b) 1
