문의 감사합니다. 계산기에는 역함수 기능이 없더군요.. 삼각함수를 그려두고,, sin x = 4/5 라고 하면요... 아래 테이블에서.. 4/5 에 해당하는 0.8에 해당하는 sin x 의 값을 찾아보세요. 약 54 정도에서 x 의 값이 정해지지요.. 이값이 각도 값입니다. 반대편은 90-54 지요.. 당시 알려 드린 수식은 엑셀에서 사용해보세요. x sin x cos x tan x 0 0.00000000 1.00000000 ** 1 0.01745240 0.99984769 0.01745506 2 0.03489949 0.99939082 0.03492076 3 0.05233595 0.99862953 0.05240777 4 0.06975647 0.99756405 0.06992681 5 0.08715574 0.99619469 0.08748866 6 0.10452846 0.99452189 0.10510423 7 0.12186934 0.99254615 0.12278456 8 0.13917310 0.99026806 0.14054083 9 0.15643446 0.98768834 0.15838444 10 0.17364817 0.98480775 0.17632698 11 0.19080899 0.98162718 0.19438030 12 0.20791169 0.97814760 0.21255656 13 0.22495105 0.97437006 0.23086819 14 0.24192189 0.97029572 0.24932800 15 0.25881904 0.96592582 0.26794919 16 0.27563735 0.96126169 0.28674538 17 0.29237170 0.95630475 0.30573068 18 0.30901699 0.95105651 0.32491969 19 0.32556815 0.94551857 0.34432761 20 0.34202014 0.93969262 0.36397023 21 0.35836794 0.93358042 0.38386403 22 0.37460659 0.92718385 0.40402622 23 0.39073112 0.92050485 0.42447481 24 0.40673664 0.91354545 0.44522868 25 0.42261826 0.90630778 0.46630765 26 0.43837114 0.89879404 0.48773258 27 0.45399049 0.89100652 0.50952544 28 0.46947156 0.88294759 0.53170943 29 0.48480962 0.87461970 0.55430905 30 0.49999999 0.86602540 0.57735026 31 0.51503807 0.85716730 0.60086061 32 0.52991926 0.84804809 0.62486935 33 0.54463903 0.83867056 0.64940759 34 0.55919290 0.82903757 0.67450851 35 0.57357643 0.81915204 0.70020753 36 0.58778525 0.80901699 0.72654252 37 0.60181502 0.79863551 0.75355405 38 0.61566147 0.78801075 0.78128562 39 0.62932039 0.77714596 0.80978403 40 0.64278760 0.76604444 0.83909963 41 0.65605902 0.75470958 0.86928673 42 0.66913060 0.74314482 0.90040404 43 0.68199836 0.73135370 0.93251508 44 0.69465837 0.71933980 0.96568877 45 0.70710678 0.70710678 0.99999999 46 0.71933980 0.69465837 1.03553031 47 0.73135370 0.68199836 1.07236870 48 0.74314482 0.66913060 1.11061251 49 0.75470958 0.65605902 1.15036840 50 0.76604444 0.64278760 1.19175359 51 0.77714596 0.62932039 1.23489715 52 0.78801075 0.61566147 1.27994163 53 0.79863551 0.60181502 1.32704482 54 0.80901699 0.58778525 1.37638192 55 0.81915204 0.57357643 1.42814800 56 0.82903757 0.55919290 1.48256096 57 0.83867056 0.54463903 1.53986496 58 0.84804809 0.52991926 1.60033452 59 0.85716730 0.51503807 1.66427948 60 0.86602540 0.50000000 1.73205080 61 0.87461970 0.48480962 1.80404775 62 0.88294759 0.46947156 1.88072646 63 0.89100652 0.45399049 1.96261050 64 0.89879404 0.43837114 2.05030384 65 0.90630778 0.42261826 2.14450692 66 0.91354545 0.40673664 2.24603677 67 0.92050485 0.39073112 2.35585236 68 0.92718385 0.37460659 2.47508685 69 0.93358042 0.35836794 2.60508906 70 0.93969262 0.34202014 2.74747741 71 0.94551857 0.32556815 2.90421087 72 0.95105651 0.30901699 3.07768353 73 0.95630475 0.29237170 3.27085261 74 0.96126169 0.27563735 3.48741444 75 0.96592582 0.25881904 3.73205080 76 0.97029572 0.24192189 4.01078093 77 0.97437006 0.22495105 4.33147587 78 0.97814760 0.20791169 4.70463010 79 0.98162718 0.19080899 5.14455401 80 0.98480775 0.17364817 5.67128181 81 0.98768834 0.15643446 6.31375151 82 0.99026806 0.13917310 7.11536972 83 0.99254615 0.12186934 8.14434642 84 0.99452189 0.10452846 9.51436445 85 0.99619469 0.08715574 11.43005229 86 0.99756405 0.06975647 14.30066624 87 0.99862953 0.05233595 19.08113667 88 0.99939082 0.03489949 28.63625324 89 0.99984769 0.01745240 57.28996148 90 1.00000000 0.00000000 ** 91 0.99984769 -0.01745240 -57.28996177 92 0.99939082 -0.03489949 -28.63625332 93 0.99862953 -0.05233595 -19.08113670 94 0.99756405 -0.06975647 -14.30066626 95 0.99619469 -0.08715574 -11.43005230 96 0.99452189 -0.10452846 -9.51436445 97 0.99254615 -0.12186934 -8.14434643 98 0.99026806 -0.13917310 -7.11536972 99 0.98768834 -0.15643446 -6.31375151 100 0.98480775 -0.17364817 -5.67128182 101 0.98162718 -0.19080899 -5.14455401 102 0.97814760 -0.20791169 -4.70463011 103 0.97437006 -0.22495105 -4.33147587 104 0.97029572 -0.24192189 -4.01078093 105 0.96592582 -0.25881904 -3.73205080 106 0.96126169 -0.27563735 -3.48741444 107 0.95630475 -0.29237170 -3.27085261 108 0.95105651 -0.30901699 -3.07768353 109 0.94551857 -0.32556815 -2.90421087 110 0.93969262 -0.34202014 -2.74747741 111 0.93358042 -0.35836794 -2.60508906 112 0.92718385 -0.37460659 -2.47508685 113 0.92050485 -0.39073112 -2.35585236 114 0.91354545 -0.40673664 -2.24603677 115 0.90630778 -0.42261826 -2.14450692 116 0.89879404 -0.43837114 -2.05030384 117 0.89100652 -0.45399049 -1.96261050 118 0.88294759 -0.46947156 -1.88072646 119 0.87461970 -0.48480962 -1.80404775 120 0.86602540 -0.49999999 -1.73205080 121 0.85716730 -0.51503807 -1.66427948 122 0.84804809 -0.52991926 -1.60033452 123 0.83867056 -0.54463903 -1.53986496 124 0.82903757 -0.55919290 -1.48256096 125 0.81915204 -0.57357643 -1.42814800 126 0.80901699 -0.58778525 -1.37638192 127 0.79863551 -0.60181502 -1.32704482 128 0.78801075 -0.61566147 -1.27994163 129 0.77714596 -0.62932039 -1.23489715 130 0.76604444 -0.64278760 -1.19175359 131 0.75470958 -0.65605902 -1.15036840 132 0.74314482 -0.66913060 -1.11061251 133 0.73135370 -0.68199836 -1.07236871 134 0.71933980 -0.69465837 -1.03553031 135 0.70710678 -0.70710678 -1.00000000 136 0.69465837 -0.71933980 -0.96568877 137 0.68199836 -0.73135370 -0.93251508 138 0.66913060 -0.74314482 -0.90040404 139 0.65605902 -0.75470958 -0.86928673 140 0.64278760 -0.76604444 -0.83909963 141 0.62932039 -0.77714596 -0.80978403 142 0.61566147 -0.78801075 -0.78128562 143 0.60181502 -0.79863551 -0.75355405 144 0.58778525 -0.80901699 -0.72654252 145 0.57357643 -0.81915204 -0.70020753 146 0.55919290 -0.82903757 -0.67450851 147 0.54463903 -0.83867056 -0.64940759 148 0.52991926 -0.84804809 -0.62486935 149 0.51503807 -0.85716730 -0.60086061 150 0.50000000 -0.86602540 -0.57735026 151 0.48480962 -0.87461970 -0.55430905 152 0.46947156 -0.88294759 -0.53170943 153 0.45399049 -0.89100652 -0.50952544 154 0.43837114 -0.89879404 -0.48773258 155 0.42261826 -0.90630778 -0.46630765 156 0.40673664 -0.91354545 -0.44522868 157 0.39073112 -0.92050485 -0.42447481 158 0.37460659 -0.92718385 -0.40402622 159 0.35836794 -0.93358042 -0.38386403 160 0.34202014 -0.93969262 -0.36397023 161 0.32556815 -0.94551857 -0.34432761 162 0.30901699 -0.95105651 -0.32491969 163 0.29237170 -0.95630475 -0.30573068 164 0.27563735 -0.96126169 -0.28674538 165 0.25881904 -0.96592582 -0.26794919 166 0.24192189 -0.97029572 -0.24932800 167 0.22495105 -0.97437006 -0.23086819 168 0.20791169 -0.97814760 -0.21255656 169 0.19080899 -0.98162718 -0.19438030 170 0.17364817 -0.98480775 -0.17632698 171 0.15643446 -0.98768834 -0.15838444 172 0.13917310 -0.99026806 -0.14054083 173 0.12186934 -0.99254615 -0.12278456 174 0.10452846 -0.99452189 -0.10510423 175 0.08715574 -0.99619469 -0.08748866 176 0.06975647 -0.99756405 -0.06992681 177 0.05233595 -0.99862953 -0.05240777 178 0.03489949 -0.99939082 -0.03492076 179 0.01745240 -0.99984769 -0.01745506 180 0.00000000 -1.00000000 ** 181 -0.01745240 -0.99984769 0.01745506 182 -0.03489949 -0.99939082 0.03492076 183 -0.05233595 -0.99862953 0.05240777 184 -0.06975647 -0.99756405 0.06992681 185 -0.08715574 -0.99619469 0.08748866 186 -0.10452846 -0.99452189 0.10510423 187 -0.12186934 -0.99254615 0.12278456 188 -0.13917310 -0.99026806 0.14054083 189 -0.15643446 -0.98768834 0.15838444 190 -0.17364817 -0.98480775 0.17632698 191 -0.19080899 -0.98162718 0.19438030 192 -0.20791169 -0.97814760 0.21255656 193 -0.22495105 -0.97437006 0.23086819 194 -0.24192189 -0.97029572 0.24932800 195 -0.25881904 -0.96592582 0.26794919 196 -0.27563735 -0.96126169 0.28674538 197 -0.29237170 -0.95630475 0.30573068 198 -0.30901699 -0.95105651 0.32491969 199 -0.32556815 -0.94551857 0.34432761 200 -0.34202014 -0.93969262 0.36397023 201 -0.35836794 -0.93358042 0.38386403 202 -0.37460659 -0.92718385 0.40402622 203 -0.39073112 -0.92050485 0.42447481 204 -0.40673664 -0.91354545 0.44522868 205 -0.42261826 -0.90630778 0.46630765 206 -0.43837114 -0.89879404 0.48773258 207 -0.45399049 -0.89100652 0.50952544 208 -0.46947156 -0.88294759 0.53170943 209 -0.48480962 -0.87461970 0.55430905 210 -0.49999999 -0.86602540 0.57735026 211 -0.51503807 -0.85716730 0.60086061 212 -0.52991926 -0.84804809 0.62486935 213 -0.54463903 -0.83867056 0.64940759 214 -0.55919290 -0.82903757 0.67450851 215 -0.57357643 -0.81915204 0.70020753 216 -0.58778525 -0.80901699 0.72654252 217 -0.60181502 -0.79863551 0.75355404 218 -0.61566147 -0.78801075 0.78128562 219 -0.62932039 -0.77714596 0.80978403 220 -0.64278760 -0.76604444 0.83909963 221 -0.65605902 -0.75470958 0.86928673 222 -0.66913060 -0.74314482 0.90040404 223 -0.68199835 -0.73135370 0.93251508 224 -0.69465837 -0.71933980 0.96568877 225 -0.70710678 -0.70710678 0.99999999 226 -0.71933980 -0.69465837 1.03553031 227 -0.73135370 -0.68199836 1.07236870 228 -0.74314482 -0.66913060 1.11061251 229 -0.75470958 -0.65605902 1.15036840 230 -0.76604444 -0.64278760 1.19175359 231 -0.77714596 -0.62932039 1.23489715 232 -0.78801075 -0.61566147 1.27994163 233 -0.79863550 -0.60181502 1.32704482 234 -0.80901699 -0.58778525 1.37638192 235 -0.81915204 -0.57357643 1.42814800 236 -0.82903757 -0.55919290 1.48256096 237 -0.83867056 -0.54463903 1.53986496 238 -0.84804809 -0.52991926 1.60033452 239 -0.85716730 -0.51503807 1.66427948 240 -0.86602540 -0.50000000 1.73205080 241 -0.87461970 -0.48480962 1.80404775 242 -0.88294759 -0.46947156 1.88072646 243 -0.89100652 -0.45399049 1.96261050 244 -0.89879404 -0.43837114 2.05030384 245 -0.90630778 -0.42261826 2.14450691 246 -0.91354545 -0.40673664 2.24603677 247 -0.92050485 -0.39073112 2.35585236 248 -0.92718385 -0.37460659 2.47508685 249 -0.93358042 -0.35836794 2.60508906 250 -0.93969262 -0.34202014 2.74747741 251 -0.94551857 -0.32556815 2.90421087 252 -0.95105651 -0.30901699 3.07768353 253 -0.95630475 -0.29237170 3.27085261 254 -0.96126169 -0.27563735 3.48741444 255 -0.96592582 -0.25881904 3.73205080 256 -0.97029572 -0.24192189 4.01078093 257 -0.97437006 -0.22495105 4.33147587 258 -0.97814760 -0.20791169 4.70463010 259 -0.98162718 -0.19080899 5.14455401 260 -0.98480775 -0.17364817 5.67128181 261 -0.98768834 -0.15643446 6.31375150 262 -0.99026806 -0.13917310 7.11536971 263 -0.99254615 -0.12186934 8.14434641 264 -0.99452189 -0.10452846 9.51436444 265 -0.99619469 -0.08715574 11.43005228 266 -0.99756405 -0.06975647 14.30066622 267 -0.99862953 -0.05233595 19.08113663 268 -0.99939082 -0.03489949 28.63625317 269 -0.99984769 -0.01745240 57.28996119 270 -1.00000000 -0.00000000 ** 271 -0.99984769 0.01745240 -57.28996207 272 -0.99939082 0.03489949 -28.63625339 273 -0.99862953 0.05233595 -19.08113673 274 -0.99756405 0.06975647 -14.30066628 275 -0.99619469 0.08715574 -11.43005232 276 -0.99452189 0.10452846 -9.51436446 277 -0.99254615 0.12186934 -8.14434643 278 -0.99026806 0.13917310 -7.11536972 279 -0.98768834 0.15643446 -6.31375152 280 -0.98480775 0.17364817 -5.67128182 281 -0.98162718 0.19080899 -5.14455401 282 -0.97814760 0.20791169 -4.70463011 283 -0.97437006 0.22495105 -4.33147587 284 -0.97029572 0.24192189 -4.01078093 285 -0.96592582 0.25881904 -3.73205080 286 -0.96126169 0.27563735 -3.48741444 287 -0.95630475 0.29237170 -3.27085262 288 -0.95105651 0.30901699 -3.07768353 289 -0.94551857 0.32556815 -2.90421087 290 -0.93969262 0.34202014 -2.74747742 291 -0.93358042 0.35836794 -2.60508906 292 -0.92718385 0.37460659 -2.47508685 293 -0.92050485 0.39073112 -2.35585236 294 -0.91354545 0.40673664 -2.24603677 295 -0.90630778 0.42261826 -2.14450692 296 -0.89879404 0.43837114 -2.05030384 297 -0.89100652 0.45399049 -1.96261050 298 -0.88294759 0.46947156 -1.88072646 299 -0.87461970 0.48480962 -1.80404775 300 -0.86602540 0.49999999 -1.73205080 301 -0.85716730 0.51503807 -1.66427948 302 -0.84804809 0.52991926 -1.60033452 303 -0.83867056 0.54463903 -1.53986496 304 -0.82903757 0.55919290 -1.48256096 305 -0.81915204 0.57357643 -1.42814800 306 -0.80901699 0.58778525 -1.37638192 307 -0.79863551 0.60181502 -1.32704482 308 -0.78801075 0.61566147 -1.27994163 309 -0.77714596 0.62932039 -1.23489715 310 -0.76604444 0.64278760 -1.19175359 311 -0.75470958 0.65605902 -1.15036840 312 -0.74314482 0.66913060 -1.11061251 313 -0.73135370 0.68199835 -1.07236871 314 -0.71933980 0.69465837 -1.03553031 315 -0.70710678 0.70710678 -1.00000000 316 -0.69465837 0.71933980 -0.96568877 317 -0.68199836 0.73135370 -0.93251508 318 -0.66913060 0.74314482 -0.90040404 319 -0.65605902 0.75470958 -0.86928673 320 -0.64278760 0.76604444 -0.83909963 321 -0.62932039 0.77714596 -0.80978403 322 -0.61566147 0.78801075 -0.78128562 323 -0.60181502 0.79863550 -0.75355405 324 -0.58778525 0.80901699 -0.72654252 325 -0.57357643 0.81915204 -0.70020753 326 -0.55919290 0.82903757 -0.67450851 327 -0.54463903 0.83867056 -0.64940759 328 -0.52991926 0.84804809 -0.62486935 329 -0.51503807 0.85716730 -0.60086061 330 -0.50000000 0.86602540 -0.57735026 331 -0.48480962 0.87461970 -0.55430905 332 -0.46947156 0.88294759 -0.53170943 333 -0.45399049 0.89100652 -0.50952544 334 -0.43837114 0.89879404 -0.48773258 335 -0.42261826 0.90630778 -0.46630765 336 -0.40673664 0.91354545 -0.44522868 337 -0.39073112 0.92050485 -0.42447481 338 -0.37460659 0.92718385 -0.40402622 339 -0.35836794 0.93358042 -0.38386403 340 -0.34202014 0.93969262 -0.36397023 341 -0.32556815 0.94551857 -0.34432761 342 -0.30901699 0.95105651 -0.32491969 343 -0.29237170 0.95630475 -0.30573068 344 -0.27563735 0.96126169 -0.28674538 345 -0.25881904 0.96592582 -0.26794919 346 -0.24192189 0.97029572 -0.24932800 347 -0.22495105 0.97437006 -0.23086819 348 -0.20791169 0.97814760 -0.21255656 349 -0.19080899 0.98162718 -0.19438030 350 -0.17364817 0.98480775 -0.17632698 351 -0.15643446 0.98768834 -0.15838444 352 -0.13917310 0.99026806 -0.14054083 353 -0.12186934 0.99254615 -0.12278456 354 -0.10452846 0.99452189 -0.10510423 355 -0.08715574 0.99619469 -0.08748866 356 -0.06975647 0.99756405 -0.06992681 357 -0.05233595 0.99862953 -0.05240777 358 -0.03489949 0.99939082 -0.03492076 359 -0.01745240 0.99984769 -0.01745506 360 -0.00000000 1.00000000 ** 도움이 되셨기를 바랍니다.