dy/dx = 1 + cos x
0 when cos x = -1
that is when x = pi
d^2y/dx^2 = -sin x
-sin x = 0 when x = pi
so this is not a max or min but a point of inflection
3. Given the function defined by y = x + sinx for all x such that -π/2<=x<=3π/2
a. Find the coordinate of all maximum and minimum points on the given interval. Justify your answers.
b. Find the coordinates of all points of inflection on the given interval. Justify your answers.
please be explisive!
thanks!
2 answers
now look at the ends
at x = - pi/2
y = - pi/2 + sin(-pi/2) = -pi/2 -1
minimum I bet
at x = 3 pi/2
y = 3 pi/2 + sin (3 pi/2) = 3 pi/2 -1
maximum
at x = - pi/2
y = - pi/2 + sin(-pi/2) = -pi/2 -1
minimum I bet
at x = 3 pi/2
y = 3 pi/2 + sin (3 pi/2) = 3 pi/2 -1
maximum