Find the gradient of the curve y = x^2 - 4x at the point where x = 3.
Answer and explanation
Correct answer: B. 2
- Step 1: dy/dx = 2x - 4. Step 2. At x = 3 the gradient is 2(3) - 4 = 2. Answer: 2. Why not the others: -3 is the y-value at x = 3, not the gradient, 6 forgets the -4, and 3 is the x-value.
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