4.
\frac{\mathrm{d^2y} }{\mathrm{d} x^2} = 6
Integrating, we get:
\frac{\mathrm{dy} }{\mathrm{d} x} = 6x + C_1
In order to find the value of this constant , we need to understand that the gradient of the tangent at (-1,3) is perpendicular to the gradient of the line 2x + 4y - 3 = 0...