Find the intervals in which the function f given by `f(x)=sin x + cos x(0 le x le 2 pi)` is decreasing

Find the intervals in which the function f given by f(x)=sin x + cos x(0 le x le 2 pi) is increasing

Find the intervals in which the function f given by f(x)=sin x + cos x, 0 le x le 2 pi is Increasing or Decreasing.

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

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

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

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

Find the interval in which the function f given by f(x)=sin2x+cos2x, 0lexlepi is strictly decreasing.