hi, my question is: the equation of a curve is find the gradient of the curve

a) at the point where the curve crosses the y-axis,

b) at each of the points where the curve crosses the x-axis

for a) i expanded the brackets then differentiated:

since x is zero on the y-axis the answer must be -10 and my book confirms this.

for b) i just made it but i don't think this is going in the right direction as the answer the book gives is "6 and -6"

could someone show me how its done please?

thanks, mark