Chapter 2 - Differentiation - 2.3 Exercises - Page 128: 126

$-12-x(12x)-2(66x^2-6)$ $=(12-12)+(-12x^2-12x^2)$ $=-24x^2.$

Using the Power Rule: $y'=6x^2-6.$ Using the Power Rule: $y''=\dfrac{d}{dx}y'=12x.$ Using the Power Rule: $y'''=\dfrac{d}{dx}y''=12.$ $-12-x(12x)-2(66x^2-6)$ $=(12-12)+(-12x^2-12x^2)$ $=-24x^2.$