What is the equation of the tangent to the curve y = x^2 + x at the point where x = 1?
Answer and explanation
Correct answer: A. y = 3x - 1
- Step 1: f(1) = 2 and f'(x) = 2x + 1, so the slope is f'(1) = 3.
- Step 2: y = 3(x - 1) + 2, which simplifies to y = 3x - 1.
Answer
y = 3x - 1.
Why not the others: The other lines confuse the y-intercept with the value of f at that point, swap the slope with that value, or reverse the sign of the slope.
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