(i) To find the gradient, we need to differentiate the equation implicitly with respect to \(x\):
\(\frac{d}{dx}(3x^2) - \frac{d}{dx}(4xy) + \frac{d}{dx}(y^2) = \frac{d}{dx}(45)\).
This gives \(6x - (4y + 4x\frac{dy}{dx}) + 2y\frac{dy}{dx} = 0\).
Rearrange to find \(\frac{dy}{dx}\):
\(6x - 4y = (4x - 2y)\frac{dy}{dx}\).
\(\frac{dy}{dx} = \frac{6x - 4y}{4x - 2y}\).
Substitute \(x = 2\) and \(y = -3\):
\(\frac{dy}{dx} = \frac{6(2) - 4(-3)}{4(2) - 2(-3)} = \frac{12 + 12}{8 + 6} = \frac{24}{14} = \frac{12}{7}\).
(ii) To show there are no points where the gradient is 1, set \(\frac{dy}{dx} = 1\):
\(\frac{6x - 4y}{4x - 2y} = 1\).
This implies \(6x - 4y = 4x - 2y\).
Simplifying gives \(2x = 2y\) or \(y = x\).
Substitute \(y = x\) into the original equation:
\(3x^2 - 4x^2 + x^2 = 45\).
This simplifies to \(0 = 45\), a contradiction.
Therefore, there are no points on the curve where the gradient is 1.