Given the inequality:
$$\sin{\left(t \right)} \geq \frac{1}{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\sin{\left(t \right)} = \frac{1}{2}$$
Solve:
Given the equation
$$\sin{\left(t \right)} = \frac{1}{2}$$
transform
$$\sin{\left(t \right)} - \frac{1}{2} = 0$$
$$\sin{\left(t \right)} - \frac{1}{2} = 0$$
Do replacement
$$w = \sin{\left(t \right)}$$
Move free summands (without w)
from left part to right part, we given:
$$w = \frac{1}{2}$$
We get the answer: w = 1/2
do backward replacement
$$\sin{\left(t \right)} = w$$
substitute w:
$$k_{1} = 38.2227106186758$$
$$k_{2} = -28.7979326579064$$
$$k_{3} = -47.6474885794452$$
$$k_{4} = 21.4675497995303$$
$$k_{5} = 34.0339204138894$$
$$k_{6} = -74.8746249105567$$
$$k_{7} = -627.79493194236$$
$$k_{8} = 71.733032256967$$
$$k_{9} = 78.0162175641465$$
$$k_{10} = 44.5058959258554$$
$$k_{11} = 40.317105721069$$
$$k_{12} = -16.2315620435473$$
$$k_{13} = -60.2138591938044$$
$$k_{14} = 84.2994028713261$$
$$k_{15} = -56.025068989018$$
$$k_{16} = 0.523598775598299$$
$$k_{17} = 8.90117918517108$$
$$k_{18} = 50.789081233035$$
$$k_{19} = 75.9218224617533$$
$$k_{20} = -37.1755130674792$$
$$k_{21} = 6.80678408277789$$
$$k_{22} = -41.3643032722656$$
$$k_{23} = 31.9395253114962$$
$$k_{24} = 63.3554518473942$$
$$k_{25} = -62.3082542961976$$
$$k_{26} = -24.60914245312$$
$$k_{27} = -5.75958653158129$$
$$k_{28} = -18.3259571459405$$
$$k_{29} = 90.5825881785057$$
$$k_{30} = -100.007366139275$$
$$k_{31} = -79.0634151153431$$
$$k_{32} = -85.3466004225227$$
$$k_{33} = 94.7713783832921$$
$$k_{34} = -97.9129710368819$$
$$k_{35} = -9.94837673636768$$
$$k_{36} = 25.6563400043166$$
$$k_{37} = -81.1578102177363$$
$$k_{38} = -30.8923277602996$$
$$k_{39} = -72.7802298081635$$
$$k_{40} = 46.6002910282486$$
$$k_{41} = -91.6297857297023$$
$$k_{42} = 13.0899693899575$$
$$k_{43} = 52.8834763354282$$
$$k_{44} = 96.8657734856853$$
$$k_{45} = -2650.98060085419$$
$$k_{46} = 19.3731546971371$$
$$k_{47} = 2.61799387799149$$
$$k_{48} = -35.081117965086$$
$$k_{49} = 57.0722665402146$$
$$k_{50} = 27.7507351067098$$
$$k_{51} = 138.753675533549$$
$$k_{52} = 101.054563690472$$
$$k_{53} = -4454.25478401473$$
$$k_{54} = -12.0427718387609$$
$$k_{55} = -68.5914396033772$$
$$k_{56} = -87.4409955249159$$
$$k_{57} = -22.5147473507269$$
$$k_{58} = 88.4881930761125$$
$$k_{59} = 15.1843644923507$$
$$k_{60} = -49.7418836818384$$
$$k_{61} = 65.4498469497874$$
$$k_{62} = 82.2050077689329$$
$$k_{63} = -53.9306738866248$$
$$k_{64} = 59.1666616426078$$
$$k_{65} = -3.66519142918809$$
$$k_{66} = 17438.4572213013$$
$$k_{67} = 69.6386371545737$$
$$k_{68} = -93.7241808320955$$
$$k_{69} = -66.497044500984$$
$$k_{70} = -43.4586983746588$$
$$k_{71} = 134.564885328763$$
$$k_{1} = 38.2227106186758$$
$$k_{2} = -28.7979326579064$$
$$k_{3} = -47.6474885794452$$
$$k_{4} = 21.4675497995303$$
$$k_{5} = 34.0339204138894$$
$$k_{6} = -74.8746249105567$$
$$k_{7} = -627.79493194236$$
$$k_{8} = 71.733032256967$$
$$k_{9} = 78.0162175641465$$
$$k_{10} = 44.5058959258554$$
$$k_{11} = 40.317105721069$$
$$k_{12} = -16.2315620435473$$
$$k_{13} = -60.2138591938044$$
$$k_{14} = 84.2994028713261$$
$$k_{15} = -56.025068989018$$
$$k_{16} = 0.523598775598299$$
$$k_{17} = 8.90117918517108$$
$$k_{18} = 50.789081233035$$
$$k_{19} = 75.9218224617533$$
$$k_{20} = -37.1755130674792$$
$$k_{21} = 6.80678408277789$$
$$k_{22} = -41.3643032722656$$
$$k_{23} = 31.9395253114962$$
$$k_{24} = 63.3554518473942$$
$$k_{25} = -62.3082542961976$$
$$k_{26} = -24.60914245312$$
$$k_{27} = -5.75958653158129$$
$$k_{28} = -18.3259571459405$$
$$k_{29} = 90.5825881785057$$
$$k_{30} = -100.007366139275$$
$$k_{31} = -79.0634151153431$$
$$k_{32} = -85.3466004225227$$
$$k_{33} = 94.7713783832921$$
$$k_{34} = -97.9129710368819$$
$$k_{35} = -9.94837673636768$$
$$k_{36} = 25.6563400043166$$
$$k_{37} = -81.1578102177363$$
$$k_{38} = -30.8923277602996$$
$$k_{39} = -72.7802298081635$$
$$k_{40} = 46.6002910282486$$
$$k_{41} = -91.6297857297023$$
$$k_{42} = 13.0899693899575$$
$$k_{43} = 52.8834763354282$$
$$k_{44} = 96.8657734856853$$
$$k_{45} = -2650.98060085419$$
$$k_{46} = 19.3731546971371$$
$$k_{47} = 2.61799387799149$$
$$k_{48} = -35.081117965086$$
$$k_{49} = 57.0722665402146$$
$$k_{50} = 27.7507351067098$$
$$k_{51} = 138.753675533549$$
$$k_{52} = 101.054563690472$$
$$k_{53} = -4454.25478401473$$
$$k_{54} = -12.0427718387609$$
$$k_{55} = -68.5914396033772$$
$$k_{56} = -87.4409955249159$$
$$k_{57} = -22.5147473507269$$
$$k_{58} = 88.4881930761125$$
$$k_{59} = 15.1843644923507$$
$$k_{60} = -49.7418836818384$$
$$k_{61} = 65.4498469497874$$
$$k_{62} = 82.2050077689329$$
$$k_{63} = -53.9306738866248$$
$$k_{64} = 59.1666616426078$$
$$k_{65} = -3.66519142918809$$
$$k_{66} = 17438.4572213013$$
$$k_{67} = 69.6386371545737$$
$$k_{68} = -93.7241808320955$$
$$k_{69} = -66.497044500984$$
$$k_{70} = -43.4586983746588$$
$$k_{71} = 134.564885328763$$
This roots
$$k_{53} = -4454.25478401473$$
$$k_{45} = -2650.98060085419$$
$$k_{7} = -627.79493194236$$
$$k_{30} = -100.007366139275$$
$$k_{34} = -97.9129710368819$$
$$k_{68} = -93.7241808320955$$
$$k_{41} = -91.6297857297023$$
$$k_{56} = -87.4409955249159$$
$$k_{32} = -85.3466004225227$$
$$k_{37} = -81.1578102177363$$
$$k_{31} = -79.0634151153431$$
$$k_{6} = -74.8746249105567$$
$$k_{39} = -72.7802298081635$$
$$k_{55} = -68.5914396033772$$
$$k_{69} = -66.497044500984$$
$$k_{25} = -62.3082542961976$$
$$k_{13} = -60.2138591938044$$
$$k_{15} = -56.025068989018$$
$$k_{63} = -53.9306738866248$$
$$k_{60} = -49.7418836818384$$
$$k_{3} = -47.6474885794452$$
$$k_{70} = -43.4586983746588$$
$$k_{22} = -41.3643032722656$$
$$k_{20} = -37.1755130674792$$
$$k_{48} = -35.081117965086$$
$$k_{38} = -30.8923277602996$$
$$k_{2} = -28.7979326579064$$
$$k_{26} = -24.60914245312$$
$$k_{57} = -22.5147473507269$$
$$k_{28} = -18.3259571459405$$
$$k_{12} = -16.2315620435473$$
$$k_{54} = -12.0427718387609$$
$$k_{35} = -9.94837673636768$$
$$k_{27} = -5.75958653158129$$
$$k_{65} = -3.66519142918809$$
$$k_{16} = 0.523598775598299$$
$$k_{47} = 2.61799387799149$$
$$k_{21} = 6.80678408277789$$
$$k_{17} = 8.90117918517108$$
$$k_{42} = 13.0899693899575$$
$$k_{59} = 15.1843644923507$$
$$k_{46} = 19.3731546971371$$
$$k_{4} = 21.4675497995303$$
$$k_{36} = 25.6563400043166$$
$$k_{50} = 27.7507351067098$$
$$k_{23} = 31.9395253114962$$
$$k_{5} = 34.0339204138894$$
$$k_{1} = 38.2227106186758$$
$$k_{11} = 40.317105721069$$
$$k_{10} = 44.5058959258554$$
$$k_{40} = 46.6002910282486$$
$$k_{18} = 50.789081233035$$
$$k_{43} = 52.8834763354282$$
$$k_{49} = 57.0722665402146$$
$$k_{64} = 59.1666616426078$$
$$k_{24} = 63.3554518473942$$
$$k_{61} = 65.4498469497874$$
$$k_{67} = 69.6386371545737$$
$$k_{8} = 71.733032256967$$
$$k_{19} = 75.9218224617533$$
$$k_{9} = 78.0162175641465$$
$$k_{62} = 82.2050077689329$$
$$k_{14} = 84.2994028713261$$
$$k_{58} = 88.4881930761125$$
$$k_{29} = 90.5825881785057$$
$$k_{33} = 94.7713783832921$$
$$k_{44} = 96.8657734856853$$
$$k_{52} = 101.054563690472$$
$$k_{71} = 134.564885328763$$
$$k_{51} = 138.753675533549$$
$$k_{66} = 17438.4572213013$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$k_{0} \leq k_{53}$$
For example, let's take the point
$$k_{0} = k_{53} - \frac{1}{10}$$
=
$$-4454.25478401473 + - \frac{1}{10}$$
=
$$-4454.35478401473$$
substitute to the expression
$$\sin{\left(t \right)} \geq \frac{1}{2}$$
$$\sin{\left(t \right)} \geq \frac{1}{2}$$
sin(t) >= 1/2
Then
$$k \leq -4454.25478401473$$
no execute
one of the solutions of our inequality is:
$$k \geq -4454.25478401473 \wedge k \leq -2650.98060085419$$
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k53 k45 k7 k30 k34 k68 k41 k56 k32 k37 k31 k6 k39 k55 k69 k25 k13 k15 k63 k60 k3 k70 k22 k20 k48 k38 k2 k26 k57 k28 k12 k54 k35 k27 k65 k16 k47 k21 k17 k42 k59 k46 k4 k36 k50 k23 k5 k1 k11 k10 k40 k18 k43 k49 k64 k24 k61 k67 k8 k19 k9 k62 k14 k58 k29 k33 k44 k52 k71 k51 k66Other solutions will get with the changeover to the next point
etc.
The answer:
$$k \geq -4454.25478401473 \wedge k \leq -2650.98060085419$$
$$k \geq -627.79493194236 \wedge k \leq -100.007366139275$$
$$k \geq -97.9129710368819 \wedge k \leq -93.7241808320955$$
$$k \geq -91.6297857297023 \wedge k \leq -87.4409955249159$$
$$k \geq -85.3466004225227 \wedge k \leq -81.1578102177363$$
$$k \geq -79.0634151153431 \wedge k \leq -74.8746249105567$$
$$k \geq -72.7802298081635 \wedge k \leq -68.5914396033772$$
$$k \geq -66.497044500984 \wedge k \leq -62.3082542961976$$
$$k \geq -60.2138591938044 \wedge k \leq -56.025068989018$$
$$k \geq -53.9306738866248 \wedge k \leq -49.7418836818384$$
$$k \geq -47.6474885794452 \wedge k \leq -43.4586983746588$$
$$k \geq -41.3643032722656 \wedge k \leq -37.1755130674792$$
$$k \geq -35.081117965086 \wedge k \leq -30.8923277602996$$
$$k \geq -28.7979326579064 \wedge k \leq -24.60914245312$$
$$k \geq -22.5147473507269 \wedge k \leq -18.3259571459405$$
$$k \geq -16.2315620435473 \wedge k \leq -12.0427718387609$$
$$k \geq -9.94837673636768 \wedge k \leq -5.75958653158129$$
$$k \geq -3.66519142918809 \wedge k \leq 0.523598775598299$$
$$k \geq 2.61799387799149 \wedge k \leq 6.80678408277789$$
$$k \geq 8.90117918517108 \wedge k \leq 13.0899693899575$$
$$k \geq 15.1843644923507 \wedge k \leq 19.3731546971371$$
$$k \geq 21.4675497995303 \wedge k \leq 25.6563400043166$$
$$k \geq 27.7507351067098 \wedge k \leq 31.9395253114962$$
$$k \geq 34.0339204138894 \wedge k \leq 38.2227106186758$$
$$k \geq 40.317105721069 \wedge k \leq 44.5058959258554$$
$$k \geq 46.6002910282486 \wedge k \leq 50.789081233035$$
$$k \geq 52.8834763354282 \wedge k \leq 57.0722665402146$$
$$k \geq 59.1666616426078 \wedge k \leq 63.3554518473942$$
$$k \geq 65.4498469497874 \wedge k \leq 69.6386371545737$$
$$k \geq 71.733032256967 \wedge k \leq 75.9218224617533$$
$$k \geq 78.0162175641465 \wedge k \leq 82.2050077689329$$
$$k \geq 84.2994028713261 \wedge k \leq 88.4881930761125$$
$$k \geq 90.5825881785057 \wedge k \leq 94.7713783832921$$
$$k \geq 96.8657734856853 \wedge k \leq 101.054563690472$$
$$k \geq 134.564885328763 \wedge k \leq 138.753675533549$$
$$k \geq 17438.4572213013$$