Q11)
The curve C has equation
y = x^3 - 2x^2 - x + 9
The point P has co-ordinates (2,7)
a)Show that P lies on C
b)Find the equation of the tangent to c at P
The point Q also lies on C
Given that the tangent to c at Q is perpendicular to the tangent to c at P
c) Show that x-cordinate of Q is 1/3 (2+sqrt 6)
I need help in part c pleaseeee!!!!!!!!!!!!!!!
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