For the first one, you need to start by differentiating x^2.
Differentiating it gives you "dy/dy", also known as the gradient function.
The method of differentiating, is "Multiply by the current power, and then decrease the power by 1."
So to differentiate x^2, you multiply by 2, and decrease the power fromk 2 to 1; hence the result is 2x.
Youy would then need to substitute the value of x in to find the gradient at that point.
For x^3, it is a similar process. Start by multiplying by the power, so multiply by 3, and then reduce the power from 3 to 2. Hence the result is 3x^2. Again sub in values of x to find the gradient.