Differentiate y = 3x^4 - 2x with respect to x.
Answer and explanation
Correct answer: C. dy/dx = 12x^3 - 2
- Step 1: Use the power rule: d/dx(3x^4) = 12x^3 and d/dx(2x) = 2. Step 2. So dy/dx = 12x^3 - 2. Answer: dy/dx = 12x^3 - 2. Why not the others: 12x^4 - 2 keeps the old power, 3x^3 - 2 forgets to multiply by the power, and 12x^3 - 2x leaves the x on the linear term.
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