Find the equation of the tangent to at the point where .

Answer and explanation

Correct answer: D.

  1. Step 1: At , , so the point is .
  2. Step 2: , so the gradient at is .
  3. Step 3: Tangent: , so .
Answer
.
Why not the others: does not pass through ; uses gradient 1 from forgetting the chain rule; the last uses the reciprocal gradient.

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