calculus
posted by Anonymous .
For what values of x does the graph of f have a horizontal tangent? (Use n as your integer variable. Enter your answers as a commaseparated list.)
f(x) = x − 2 sin x

horizontal tangent means slope = 0
f'(x) = 1  2cosx
12cosx=0
cosx = 1/2
x = 2kpi +/ pi/3