Evaluate the limit of (x^2 - 16)/(x - 4) as x approaches 4.
Answer and explanation
Correct answer: B. 8
- Step 1: Factorise the numerator: x^2 - 16 = (x - 4)(x + 4). Step 2. Cancel (x - 4): the limit of (x + 4) as x approaches 4 is 8. Answer: 8. Why not the others: 0: Direct substitution gives 0/0, which is indeterminate, not 0. 4: That is the value of x at the limit, not the limit of the expression. 16: That is the square of the number, not the limit.
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