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Question

Calculate the d^2y/dx^2.

y= e^-x + e^x

y' = e^x - e^-x

y'' = e^x + e^-x

Find the x-coordinace of all critical points of the given function. determine whether each critical point is a relative minimum, maximum, or neither by first applying the second derivative test, and, if the test fails by some other method.

g(x) = 2x^3 - 6x + 3
g'(x) = 6x^2 -6
g"(x) = 12x
max = -1
min = 1
critical = -1,1

Answer 1

Looks good to me.
Nice work.