The line is a tangent to the curve . Find the value of .

Answer and explanation

Correct answer: B. 5

  1. Step 1: Equate: , so . Step 2. A tangent gives one repeated root, so the discriminant is zero: . Step 3. Hence . Answer: 5. Why not the others: 6: That is the constant in the curve, not the value that makes the line tangent. 7: That adds instead of subtracting . 1: That is alone and leaves out the constant of the curve.

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