Sketch the curves with equations given in question 3 parts a, b, c and d, labelling any stationary points with their coordinates.

Data from Question 3

Find the coordinates of the points where the gradient is zero  on the curves with the given equations. Establish whether these points are local maximum points, local minimum points or points of inflection in each case.

a. y = 4x² + 6x 

b. y = 9 + x − x² 

c. y = x³ − x² − x + 1

d. y = x (x² − 4x − 3)