Find the intervals of decrease and increase for the function `f(x)=cos(pi/x)`

Find the intervals of decreases and increases for the following functions , f(x)=sin x + cos x " on" [0,2pi]

Find the interval of increasing and decreasing of the function f(x) =(log x)/(x)

Determine the intervals of increase and decrease for the following functions : f(x) = cos x - x

Determine the intervals of increase and decrease for the following functions : f(x) = (2x)/(1+x^(2))

Determine the intervals of increase and decrease for the following functions : f(x) =x^(3)+2x-5

Determine the intervals of increase and decrease for the following functions : f(x) =1/3 x^(3) -1/x

Find the interval in which the function f(x) =cos^(-1) ((1-x^(2))/(1+x^(2))) is increasing or decreasing.

Find the intervals in which the given function increases or decreases f(x)=(x^(2)+x+1)/(x^(2)-x+1)

Find the intervals in which the function f given f(x)=sin x+cos x,0<=x<=2 pi, is strictly increasing or strictly decreasing.