In order to find the extrema, we need to solve the equation
$$\frac{d}{d x} f{\left(x \right)} = 0$$
(the derivative equals zero),
and the roots of this equation are the extrema of this function:
$$\frac{d}{d x} f{\left(x \right)} = $$
the first derivative$$\left(\left(- \cot^{2}{\left(x \right)} - 1\right) \log{\left(\sin{\left(x \right)} + 1 \right)} + \frac{\cos{\left(x \right)} \cot{\left(x \right)}}{\sin{\left(x \right)} + 1}\right) \left(\sin{\left(x \right)} + 1\right)^{\cot{\left(x \right)}} = 0$$
Solve this equationThe roots of this equation
$$x_{1} = 3.89455409802898$$
$$x_{2} = 29.0272953267473$$
$$x_{3} = 74.6452622417159$$
$$x_{4} = -32.1688879803371$$
$$x_{5} = -63.584814516235$$
$$x_{6} = -76.1511851305942$$
$$x_{7} = 91.8591483985432$$
$$x_{8} = -52.6541136665873$$
$$x_{9} = 16.4609247123882$$
$$x_{10} = -96.6364108168444$$
$$x_{11} = 22.7441100195677$$
$$x_{12} = -724.954941534803$$
$$x_{13} = -57.3016292090555$$
$$x_{14} = -46.3709283594077$$
$$x_{15} = -2.38863120915061$$
$$x_{16} = -33.8045577450485$$
$$x_{17} = -19.6025173659779$$
$$x_{18} = -13.3193320587984$$
$$x_{19} = 98.1423337057228$$
$$x_{20} = 24.3797797842792$$
$$x_{21} = 47.8768512482861$$
$$x_{22} = 62.0788916273567$$
$$x_{23} = -21.2381871306894$$
$$x_{24} = -58.9372989737669$$
$$x_{25} = -77.7868548953056$$
$$x_{26} = 41.5936659411065$$
$$x_{27} = 66.7264071698248$$
$$x_{28} = 68.3620769345363$$
$$x_{29} = -69.8679998234146$$
$$x_{30} = -8.67181651633019$$
$$x_{31} = 59248.0488154944$$
$$x_{32} = -25.8857026731575$$
$$x_{33} = 104.425519012902$$
$$x_{34} = -65.2204842809465$$
$$x_{35} = -90.3532255096648$$
$$x_{36} = 99.7780034704342$$
$$x_{37} = -335.397452489669$$
$$x_{38} = 73.0095924770044$$
$$x_{39} = 18.0965944770996$$
$$x_{40} = -14.9550018235098$$
$$x_{41} = -84.0700402024852$$
$$x_{42} = -40.0877430522281$$
$$x_{43} = 30.6629650914587$$
$$x_{44} = -71.5036695881261$$
$$x_{45} = -82.4343704377738$$
$$x_{46} = 60.4432218626453$$
$$x_{47} = -27.521372437869$$
$$x_{48} = 85.5759630913636$$
$$x_{49} = 10.1777394052086$$
$$x_{50} = 11.81340916992$$
$$x_{51} = 79.292777784184$$
$$x_{52} = 54.1600365554657$$
$$x_{53} = 55.7957063201771$$
$$x_{54} = 35.3104806339269$$
The values of the extrema at the points:
(3.894554098028981, 0.292697608379478)
(29.02729532674733, 0.292697608379478)
(74.64526224171586, 3.41649528855568)
(-32.16888798033712, 3.41649528855568)
(-63.58481451623505, 3.41649528855568)
(-76.15118513059423, 3.41649528855568)
(91.8591483985432, 0.292697608379478)
(-52.6541136665873, 0.292697608379478)
(16.460924712388152, 0.292697608379477)
(-96.6364108168444, 0.292697608379478)
(22.74411001956774, 0.292697608379478)
(-724.9549415348031, 0.292697608379478)
(-57.30162920905546, 3.41649528855568)
(-46.37092835940771, 0.292697608379478)
(-2.388631209150606, 0.292697608379478)
(-33.80455774504854, 0.292697608379478)
(-19.602517365977945, 3.41649528855568)
(-13.319332058798361, 3.41649528855568)
(98.14233370572278, 0.292697608379478)
(24.379779784279158, 3.41649528855568)
(47.87685124828609, 0.292697608379478)
(62.078891627356676, 3.41649528855568)
(-21.238187130689365, 0.292697608379478)
(-58.937298973766886, 0.292697608379477)
(-77.78685489530564, 0.292697608379478)
(41.5936659411065, 0.292697608379477)
(66.72640716982484, 0.292697608379477)
(68.36207693453626, 3.41649528855568)
(-69.86799982341464, 3.41649528855568)
(-8.671816516330193, 0.292697608379478)
(59248.04881549435, 0.292697608379477)
(-25.88570267315753, 3.41649528855568)
(104.42551901290237, 0.292697608379478)
(-65.22048428094647, 0.292697608379478)
(-90.35322550966481, 0.292697608379478)
(99.7780034704342, 3.41649528855568)
(-335.3974524896687, 0.292697608379478)
(73.00959247700443, 0.292697608379477)
(18.096594477099572, 3.41649528855568)
(-14.955001823509779, 0.292697608379478)
(-84.07004020248523, 0.292697608379478)
(-40.08774305222813, 0.292697608379478)
(30.662965091458744, 3.41649528855568)
(-71.50366958812606, 0.292697608379478)
(-82.43437043777381, 3.41649528855568)
(60.44322186264526, 0.292697608379478)
(-27.52137243786895, 0.292697608379478)
(85.5759630913636, 0.292697608379478)
(10.177739405208568, 0.292697608379478)
(11.813409169919986, 3.41649528855568)
(79.29277778418403, 0.292697608379477)
(54.16003655546567, 0.292697608379478)
(55.79570632017709, 3.41649528855568)
(35.310480633926915, 0.292697608379478)
Intervals of increase and decrease of the function:Let's find intervals where the function increases and decreases, as well as minima and maxima of the function, for this let's look how the function behaves itself in the extremas and at the slightest deviation from:
Minima of the function at points:
$$x_{1} = 3.89455409802898$$
$$x_{2} = 29.0272953267473$$
$$x_{3} = 91.8591483985432$$
$$x_{4} = -52.6541136665873$$
$$x_{5} = 16.4609247123882$$
$$x_{6} = -96.6364108168444$$
$$x_{7} = 22.7441100195677$$
$$x_{8} = -724.954941534803$$
$$x_{9} = -46.3709283594077$$
$$x_{10} = -2.38863120915061$$
$$x_{11} = -33.8045577450485$$
$$x_{12} = 98.1423337057228$$
$$x_{13} = 47.8768512482861$$
$$x_{14} = -21.2381871306894$$
$$x_{15} = -58.9372989737669$$
$$x_{16} = -77.7868548953056$$
$$x_{17} = 41.5936659411065$$
$$x_{18} = 66.7264071698248$$
$$x_{19} = -8.67181651633019$$
$$x_{20} = 59248.0488154944$$
$$x_{21} = 104.425519012902$$
$$x_{22} = -65.2204842809465$$
$$x_{23} = -90.3532255096648$$
$$x_{24} = -335.397452489669$$
$$x_{25} = 73.0095924770044$$
$$x_{26} = -14.9550018235098$$
$$x_{27} = -84.0700402024852$$
$$x_{28} = -40.0877430522281$$
$$x_{29} = -71.5036695881261$$
$$x_{30} = 60.4432218626453$$
$$x_{31} = -27.521372437869$$
$$x_{32} = 85.5759630913636$$
$$x_{33} = 10.1777394052086$$
$$x_{34} = 79.292777784184$$
$$x_{35} = 54.1600365554657$$
$$x_{36} = 35.3104806339269$$
Maxima of the function at points:
$$x_{36} = 74.6452622417159$$
$$x_{36} = -32.1688879803371$$
$$x_{36} = -63.584814516235$$
$$x_{36} = -76.1511851305942$$
$$x_{36} = -57.3016292090555$$
$$x_{36} = -19.6025173659779$$
$$x_{36} = -13.3193320587984$$
$$x_{36} = 24.3797797842792$$
$$x_{36} = 62.0788916273567$$
$$x_{36} = 68.3620769345363$$
$$x_{36} = -69.8679998234146$$
$$x_{36} = -25.8857026731575$$
$$x_{36} = 99.7780034704342$$
$$x_{36} = 18.0965944770996$$
$$x_{36} = 30.6629650914587$$
$$x_{36} = -82.4343704377738$$
$$x_{36} = 11.81340916992$$
$$x_{36} = 55.7957063201771$$
Decreasing at intervals
$$\left[59248.0488154944, \infty\right)$$
Increasing at intervals
$$\left(-\infty, -724.954941534803\right]$$