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\(\lim_{x \to 2} \frac{sinxcos2 - cosxsin2}{x - 2} =\)

  • A.-1
  • B.1
  • C.4
  • D.2
  • E.0

Answer: B

The limit is 1.

The numerator is the expansion of a sine of a difference.

\[ \sin x\cos 2 - \cos x\sin 2 = \sin(x - 2) \]

So the expression is \(\frac{\sin(x - 2)}{x - 2}\), and with t = x - 2 tending to 0 it tends to \(\frac{\sin t}{t} \to 1\). The value 0 is what direct substitution gives in the numerator alone, and 2 or 4 bring the point x = 2 into the answer.

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