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

Answer and explanation

Correct answer: D.

  1. Step 1: , so the gradient at is 5, and . Step 2. Tangent: , which simplifies to . **Answer: . Why not the others:** : That uses the -coordinate of the point as the intercept. : That uses the -value as the gradient. : The sign of the intercept is reversed.

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