A curve has equation y = 2x^5 + 5x^4 1 . (a) Find: (i) dy/ dx [2 marks] (ii) d^2y/ dx^2 (b) The point on the curve where x ¼ 1 is P. (i) Determine whether y is increasing or decreasing at P, giving a reason for your answer.
a.) dy/dx+10x^4+20x^3
d^2y/dx^2=40x^3+60x^2
b.)sub in x=-1 to dy/dx=10(-1)^4+20(-1)^3
=-10
therefore, decreasing
