ExamBro
ExamBro
COMEDK · Maths · 16. Limits

\(\text { The value of } \lim _\limits{x \rightarrow 0} \dfrac{\sin (a+x)-\sin (a-x)}{x} \text { is }\)

  1. A 1
  2. B \(2 \cos a\)
  3. C 0
  4. D \(2 \sin a\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(2 \cos a\)

Step-by-step Solution

Detailed explanation

The given limit is \(L = \lim_{x \to 0} \dfrac{\sin(a+x) - \sin(a-x)}{x}\). Using the trigonometric identity \(\sin C - \sin D = 2 \cos \left( \dfrac{C+D}{2} \right) \sin \left( \dfrac{C-D}{2} \right)\), we set \(C = a+x\) and \(D = a-x\). Then…