What is the extreme f(x)=cos(x)+sin(x) ?

The extreme f(x)=cos(x)+sin(x) is Maximum(pi/4+2pin,sqrt(2)),Minimum((5pi)/4+2pin,-sqrt(2))

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extreme f(x)=cos(x)+sin(x)

extreme points

f (x) = cos (x) + sin (x)

Maximum (\frac{π}{4} + 2 πn, 2), Minimum (\frac{5 π}{4} + 2 πn, - 2)

Solution steps

Find the critical points:

x = \frac{π}{4} + 2 πn, x = \frac{5 π}{4} + 2 πn

Domain of

cos (x) + sin (x) : - \infty < x < \infty

Find intervals:

Increasing

: 2 πn \leq x < \frac{π}{4} + 2 πn,

Decreasing

: \frac{π}{4} + 2 πn < x < \frac{5 π}{4} + 2 πn,

Increasing

: \frac{5 π}{4} + 2 πn < x < 2 π + 2 πn

Plug the extreme point

x = \frac{π}{4} + 2 πn

into

cos (x) + sin (x) \Rightarrow y = 2

Maximum (\frac{π}{4} + 2 πn, 2)

Plug the extreme point

x = \frac{5 π}{4} + 2 πn

into

cos (x) + sin (x) \Rightarrow y = - 2

Minimum (\frac{5 π}{4} + 2 πn, - 2)

Maximum (\frac{π}{4} + 2 πn, 2), Minimum (\frac{5 π}{4} + 2 πn, - 2)

f (x) = x^{2} + \frac{16}{x}

f (x) = 2 x^{3} + 3 x^{2} - 120 x, 0 \leq x \leq 5

f (x) = 2 x^{3} - 6 x + 3

3 x - x^{3}

f (x, y) = y ln (- y + x)

What is the extreme f(x)=cos(x)+sin(x) ?
The extreme f(x)=cos(x)+sin(x) is Maximum(pi/4+2pin,sqrt(2)),Minimum((5pi)/4+2pin,-sqrt(2))