Metamath Proof Explorer


Theorem areacirc

Description: The area of a circle of radius R is _pi x. R ^ 2 . This is Metamath 100 proof #9. (Contributed by Brendan Leahy, 31-Aug-2017) (Revised by Brendan Leahy, 22-Sep-2017) (Revised by Brendan Leahy, 11-Jul-2018)

Ref Expression
Hypothesis areacirc.1 S = x y | x y x 2 + y 2 R 2
Assertion areacirc R 0 R area S = π R 2

Proof

Step Hyp Ref Expression
1 areacirc.1 S = x y | x y x 2 + y 2 R 2
2 opabssxp x y | x y x 2 + y 2 R 2 2
3 1 2 eqsstri S 2
4 3 a1i R 0 R S 2
5 1 areacirclem5 R 0 R t S t = if t R R 2 t 2 R 2 t 2
6 resqcl R R 2
7 6 3ad2ant1 R 0 R t R 2
8 resqcl t t 2
9 8 3ad2ant3 R 0 R t t 2
10 7 9 resubcld R 0 R t R 2 t 2
11 10 adantr R 0 R t t R R 2 t 2
12 absresq t t 2 = t 2
13 12 3ad2ant3 R 0 R t t 2 = t 2
14 13 breq1d R 0 R t t 2 R 2 t 2 R 2
15 recn t t
16 15 abscld t t
17 16 3ad2ant3 R 0 R t t
18 simp1 R 0 R t R
19 15 absge0d t 0 t
20 19 3ad2ant3 R 0 R t 0 t
21 simp2 R 0 R t 0 R
22 17 18 20 21 le2sqd R 0 R t t R t 2 R 2
23 7 9 subge0d R 0 R t 0 R 2 t 2 t 2 R 2
24 14 22 23 3bitr4d R 0 R t t R 0 R 2 t 2
25 24 biimpa R 0 R t t R 0 R 2 t 2
26 11 25 resqrtcld R 0 R t t R R 2 t 2
27 26 renegcld R 0 R t t R R 2 t 2
28 iccmbl R 2 t 2 R 2 t 2 R 2 t 2 R 2 t 2 dom vol
29 27 26 28 syl2anc R 0 R t t R R 2 t 2 R 2 t 2 dom vol
30 mblvol R 2 t 2 R 2 t 2 dom vol vol R 2 t 2 R 2 t 2 = vol * R 2 t 2 R 2 t 2
31 29 30 syl R 0 R t t R vol R 2 t 2 R 2 t 2 = vol * R 2 t 2 R 2 t 2
32 11 25 sqrtge0d R 0 R t t R 0 R 2 t 2
33 26 26 32 32 addge0d R 0 R t t R 0 R 2 t 2 + R 2 t 2
34 recn R R
35 34 sqcld R R 2
36 35 3ad2ant1 R 0 R t R 2
37 15 sqcld t t 2
38 37 3ad2ant3 R 0 R t t 2
39 36 38 subcld R 0 R t R 2 t 2
40 39 sqrtcld R 0 R t R 2 t 2
41 40 adantr R 0 R t t R R 2 t 2
42 41 41 subnegd R 0 R t t R R 2 t 2 R 2 t 2 = R 2 t 2 + R 2 t 2
43 42 breq2d R 0 R t t R 0 R 2 t 2 R 2 t 2 0 R 2 t 2 + R 2 t 2
44 26 27 subge0d R 0 R t t R 0 R 2 t 2 R 2 t 2 R 2 t 2 R 2 t 2
45 43 44 bitr3d R 0 R t t R 0 R 2 t 2 + R 2 t 2 R 2 t 2 R 2 t 2
46 33 45 mpbid R 0 R t t R R 2 t 2 R 2 t 2
47 ovolicc R 2 t 2 R 2 t 2 R 2 t 2 R 2 t 2 vol * R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
48 27 26 46 47 syl3anc R 0 R t t R vol * R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
49 31 48 eqtrd R 0 R t t R vol R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
50 26 27 resubcld R 0 R t t R R 2 t 2 R 2 t 2
51 49 50 eqeltrd R 0 R t t R vol R 2 t 2 R 2 t 2
52 volf vol : dom vol 0 +∞
53 ffn vol : dom vol 0 +∞ vol Fn dom vol
54 elpreima vol Fn dom vol R 2 t 2 R 2 t 2 vol -1 R 2 t 2 R 2 t 2 dom vol vol R 2 t 2 R 2 t 2
55 52 53 54 mp2b R 2 t 2 R 2 t 2 vol -1 R 2 t 2 R 2 t 2 dom vol vol R 2 t 2 R 2 t 2
56 29 51 55 sylanbrc R 0 R t t R R 2 t 2 R 2 t 2 vol -1
57 0mbl dom vol
58 mblvol dom vol vol = vol *
59 57 58 ax-mp vol = vol *
60 ovol0 vol * = 0
61 59 60 eqtri vol = 0
62 0re 0
63 61 62 eqeltri vol
64 elpreima vol Fn dom vol vol -1 dom vol vol
65 52 53 64 mp2b vol -1 dom vol vol
66 57 63 65 mpbir2an vol -1
67 66 a1i R 0 R t ¬ t R vol -1
68 56 67 ifclda R 0 R t if t R R 2 t 2 R 2 t 2 vol -1
69 5 68 eqeltrd R 0 R t S t vol -1
70 69 3expa R 0 R t S t vol -1
71 70 ralrimiva R 0 R t S t vol -1
72 5 fveq2d R 0 R t vol S t = vol if t R R 2 t 2 R 2 t 2
73 72 3expa R 0 R t vol S t = vol if t R R 2 t 2 R 2 t 2
74 73 mpteq2dva R 0 R t vol S t = t vol if t R R 2 t 2 R 2 t 2
75 renegcl R R
76 75 adantr R 0 R R
77 simpl R 0 R R
78 iccssre R R R R
79 76 77 78 syl2anc R 0 R R R
80 rembl dom vol
81 80 a1i R 0 R dom vol
82 fvexd R 0 R t R R vol if t R R 2 t 2 R 2 t 2 V
83 eldif t R R t ¬ t R R
84 3anass t R t t R t R t t R
85 84 a1i R 0 R t t R t t R t R t t R
86 75 3ad2ant1 R 0 R t R
87 elicc2 R R t R R t R t t R
88 86 18 87 syl2anc R 0 R t t R R t R t t R
89 simp3 R 0 R t t
90 89 18 absled R 0 R t t R R t t R
91 89 biantrurd R 0 R t R t t R t R t t R
92 90 91 bitrd R 0 R t t R t R t t R
93 85 88 92 3bitr4rd R 0 R t t R t R R
94 93 biimpd R 0 R t t R t R R
95 94 con3d R 0 R t ¬ t R R ¬ t R
96 95 3expia R 0 R t ¬ t R R ¬ t R
97 96 impd R 0 R t ¬ t R R ¬ t R
98 83 97 syl5bi R 0 R t R R ¬ t R
99 98 imp R 0 R t R R ¬ t R
100 iffalse ¬ t R if t R R 2 t 2 R 2 t 2 =
101 100 fveq2d ¬ t R vol if t R R 2 t 2 R 2 t 2 = vol
102 101 61 eqtrdi ¬ t R vol if t R R 2 t 2 R 2 t 2 = 0
103 99 102 syl R 0 R t R R vol if t R R 2 t 2 R 2 t 2 = 0
104 76 77 87 syl2anc R 0 R t R R t R t t R
105 90 biimprd R 0 R t R t t R t R
106 105 expd R 0 R t R t t R t R
107 106 3expia R 0 R t R t t R t R
108 107 3impd R 0 R t R t t R t R
109 104 108 sylbid R 0 R t R R t R
110 109 3impia R 0 R t R R t R
111 iftrue t R if t R R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
112 111 fveq2d t R vol if t R R 2 t 2 R 2 t 2 = vol R 2 t 2 R 2 t 2
113 110 112 syl R 0 R t R R vol if t R R 2 t 2 R 2 t 2 = vol R 2 t 2 R 2 t 2
114 6 3ad2ant1 R 0 R t R R R 2
115 75 78 mpancom R R R
116 115 sselda R t R R t
117 116 3adant2 R 0 R t R R t
118 117 resqcld R 0 R t R R t 2
119 114 118 resubcld R 0 R t R R R 2 t 2
120 75 87 mpancom R t R R t R t t R
121 120 adantr R 0 R t R R t R t t R
122 22 90 14 3bitr3rd R 0 R t t 2 R 2 R t t R
123 23 122 bitrd R 0 R t 0 R 2 t 2 R t t R
124 123 biimprd R 0 R t R t t R 0 R 2 t 2
125 124 expd R 0 R t R t t R 0 R 2 t 2
126 125 3expia R 0 R t R t t R 0 R 2 t 2
127 126 3impd R 0 R t R t t R 0 R 2 t 2
128 121 127 sylbid R 0 R t R R 0 R 2 t 2
129 128 3impia R 0 R t R R 0 R 2 t 2
130 119 129 resqrtcld R 0 R t R R R 2 t 2
131 130 renegcld R 0 R t R R R 2 t 2
132 131 130 28 syl2anc R 0 R t R R R 2 t 2 R 2 t 2 dom vol
133 132 30 syl R 0 R t R R vol R 2 t 2 R 2 t 2 = vol * R 2 t 2 R 2 t 2
134 119 recnd R 0 R t R R R 2 t 2
135 134 sqrtcld R 0 R t R R R 2 t 2
136 135 135 subnegd R 0 R t R R R 2 t 2 R 2 t 2 = R 2 t 2 + R 2 t 2
137 119 129 sqrtge0d R 0 R t R R 0 R 2 t 2
138 130 130 137 137 addge0d R 0 R t R R 0 R 2 t 2 + R 2 t 2
139 136 breq2d R 0 R t R R 0 R 2 t 2 R 2 t 2 0 R 2 t 2 + R 2 t 2
140 130 131 subge0d R 0 R t R R 0 R 2 t 2 R 2 t 2 R 2 t 2 R 2 t 2
141 139 140 bitr3d R 0 R t R R 0 R 2 t 2 + R 2 t 2 R 2 t 2 R 2 t 2
142 138 141 mpbid R 0 R t R R R 2 t 2 R 2 t 2
143 131 130 142 47 syl3anc R 0 R t R R vol * R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
144 135 2timesd R 0 R t R R 2 R 2 t 2 = R 2 t 2 + R 2 t 2
145 136 143 144 3eqtr4d R 0 R t R R vol * R 2 t 2 R 2 t 2 = 2 R 2 t 2
146 113 133 145 3eqtrd R 0 R t R R vol if t R R 2 t 2 R 2 t 2 = 2 R 2 t 2
147 146 3expa R 0 R t R R vol if t R R 2 t 2 R 2 t 2 = 2 R 2 t 2
148 147 mpteq2dva R 0 R t R R vol if t R R 2 t 2 R 2 t 2 = t R R 2 R 2 t 2
149 areacirclem3 R 0 R t R R 2 R 2 t 2 𝐿 1
150 148 149 eqeltrd R 0 R t R R vol if t R R 2 t 2 R 2 t 2 𝐿 1
151 79 81 82 103 150 iblss2 R 0 R t vol if t R R 2 t 2 R 2 t 2 𝐿 1
152 74 151 eqeltrd R 0 R t vol S t 𝐿 1
153 dmarea S dom area S 2 t S t vol -1 t vol S t 𝐿 1
154 4 71 152 153 syl3anbrc R 0 R S dom area
155 areaval S dom area area S = vol S t dt
156 154 155 syl R 0 R area S = vol S t dt
157 elioore t R R t
158 5 3expa R 0 R t S t = if t R R 2 t 2 R 2 t 2
159 157 158 sylan2 R 0 R t R R S t = if t R R 2 t 2 R 2 t 2
160 159 fveq2d R 0 R t R R vol S t = vol if t R R 2 t 2 R 2 t 2
161 160 itgeq2dv R 0 R R R vol S t dt = R R vol if t R R 2 t 2 R 2 t 2 dt
162 ioossre R R
163 162 a1i R 0 R R R
164 eldif t R R t ¬ t R R
165 75 rexrd R R *
166 rexr R R *
167 elioo2 R * R * t R R t R < t t < R
168 165 166 167 syl2anc R t R R t R < t t < R
169 168 3ad2ant1 R 0 R t t R R t R < t t < R
170 89 biantrurd R 0 R t R < t t < R t R < t t < R
171 89 18 absltd R 0 R t t < R R < t t < R
172 3anass t R < t t < R t R < t t < R
173 172 a1i R 0 R t t R < t t < R t R < t t < R
174 170 171 173 3bitr4rd R 0 R t t R < t t < R t < R
175 169 174 bitrd R 0 R t t R R t < R
176 175 notbid R 0 R t ¬ t R R ¬ t < R
177 18 17 lenltd R 0 R t R t ¬ t < R
178 176 177 bitr4d R 0 R t ¬ t R R R t
179 5 adantr R 0 R t R t S t = if t R R 2 t 2 R 2 t 2
180 179 fveq2d R 0 R t R t vol S t = vol if t R R 2 t 2 R 2 t 2
181 17 anim1i R 0 R t t = R t t = R
182 eqle t t = R t R
183 181 182 112 3syl R 0 R t t = R vol if t R R 2 t 2 R 2 t 2 = vol R 2 t 2 R 2 t 2
184 oveq1 t = R t 2 = R 2
185 184 adantl R 0 R t t = R t 2 = R 2
186 13 adantr R 0 R t t = R t 2 = t 2
187 185 186 eqtr3d R 0 R t t = R R 2 = t 2
188 fvoveq1 R 2 = t 2 R 2 t 2 = t 2 t 2
189 188 negeqd R 2 = t 2 R 2 t 2 = t 2 t 2
190 189 188 oveq12d R 2 = t 2 R 2 t 2 R 2 t 2 = t 2 t 2 t 2 t 2
191 8 recnd t t 2
192 191 subidd t t 2 t 2 = 0
193 192 fveq2d t t 2 t 2 = 0
194 193 negeqd t t 2 t 2 = 0
195 sqrt0 0 = 0
196 195 negeqi 0 = 0
197 neg0 0 = 0
198 196 197 eqtri 0 = 0
199 194 198 eqtrdi t t 2 t 2 = 0
200 193 195 eqtrdi t t 2 t 2 = 0
201 199 200 oveq12d t t 2 t 2 t 2 t 2 = 0 0
202 201 3ad2ant3 R 0 R t t 2 t 2 t 2 t 2 = 0 0
203 190 202 sylan9eqr R 0 R t R 2 = t 2 R 2 t 2 R 2 t 2 = 0 0
204 203 fveq2d R 0 R t R 2 = t 2 vol R 2 t 2 R 2 t 2 = vol 0 0
205 iccmbl 0 0 0 0 dom vol
206 62 62 205 mp2an 0 0 dom vol
207 mblvol 0 0 dom vol vol 0 0 = vol * 0 0
208 206 207 ax-mp vol 0 0 = vol * 0 0
209 0xr 0 *
210 iccid 0 * 0 0 = 0
211 210 fveq2d 0 * vol * 0 0 = vol * 0
212 209 211 ax-mp vol * 0 0 = vol * 0
213 ovolsn 0 vol * 0 = 0
214 62 213 ax-mp vol * 0 = 0
215 212 214 eqtri vol * 0 0 = 0
216 208 215 eqtri vol 0 0 = 0
217 204 216 eqtrdi R 0 R t R 2 = t 2 vol R 2 t 2 R 2 t 2 = 0
218 187 217 syldan R 0 R t t = R vol R 2 t 2 R 2 t 2 = 0
219 183 218 eqtrd R 0 R t t = R vol if t R R 2 t 2 R 2 t 2 = 0
220 219 ex R 0 R t t = R vol if t R R 2 t 2 R 2 t 2 = 0
221 220 adantr R 0 R t R t t = R vol if t R R 2 t 2 R 2 t 2 = 0
222 18 17 ltnled R 0 R t R < t ¬ t R
223 222 adantr R 0 R t R t R < t ¬ t R
224 simpl1 R 0 R t R t R
225 17 adantr R 0 R t R t t
226 simpr R 0 R t R t R t
227 224 225 226 leltned R 0 R t R t R < t t R
228 223 227 bitr3d R 0 R t R t ¬ t R t R
229 228 102 syl6bir R 0 R t R t t R vol if t R R 2 t 2 R 2 t 2 = 0
230 221 229 pm2.61dne R 0 R t R t vol if t R R 2 t 2 R 2 t 2 = 0
231 180 230 eqtrd R 0 R t R t vol S t = 0
232 231 ex R 0 R t R t vol S t = 0
233 178 232 sylbid R 0 R t ¬ t R R vol S t = 0
234 233 3expia R 0 R t ¬ t R R vol S t = 0
235 234 impd R 0 R t ¬ t R R vol S t = 0
236 164 235 syl5bi R 0 R t R R vol S t = 0
237 236 imp R 0 R t R R vol S t = 0
238 163 237 itgss R 0 R R R vol S t dt = vol S t dt
239 negeq R = 0 R = 0
240 239 197 eqtrdi R = 0 R = 0
241 id R = 0 R = 0
242 240 241 oveq12d R = 0 R R = 0 0
243 iooid 0 0 =
244 242 243 eqtrdi R = 0 R R =
245 244 adantl R 0 R R = 0 R R =
246 itgeq1 R R = R R vol if t R R 2 t 2 R 2 t 2 dt = vol if t R R 2 t 2 R 2 t 2 dt
247 245 246 syl R 0 R R = 0 R R vol if t R R 2 t 2 R 2 t 2 dt = vol if t R R 2 t 2 R 2 t 2 dt
248 itg0 vol if t R R 2 t 2 R 2 t 2 dt = 0
249 sq0 0 2 = 0
250 249 oveq2i π 0 2 = π 0
251 picn π
252 251 mul01i π 0 = 0
253 250 252 eqtr2i 0 = π 0 2
254 oveq1 R = 0 R 2 = 0 2
255 254 oveq2d R = 0 π R 2 = π 0 2
256 253 255 eqtr4id R = 0 0 = π R 2
257 256 adantl R 0 R R = 0 0 = π R 2
258 248 257 eqtrid R 0 R R = 0 vol if t R R 2 t 2 R 2 t 2 dt = π R 2
259 247 258 eqtrd R 0 R R = 0 R R vol if t R R 2 t 2 R 2 t 2 dt = π R 2
260 simp1 R 0 R R 0 R
261 0red R 0 R 0
262 simpr R 0 R 0 R
263 261 77 262 leltned R 0 R 0 < R R 0
264 263 biimp3ar R 0 R R 0 0 < R
265 260 264 elrpd R 0 R R 0 R +
266 265 3expa R 0 R R 0 R +
267 157 16 syl t R R t
268 267 adantl R + t R R t
269 rpre R + R
270 269 adantr R + t R R R
271 269 renegcld R + R
272 271 rexrd R + R *
273 rpxr R + R *
274 272 273 167 syl2anc R + t R R t R < t t < R
275 simpr R + t t
276 269 adantr R + t R
277 275 276 absltd R + t t < R R < t t < R
278 277 biimprd R + t R < t t < R t < R
279 278 exp4b R + t R < t t < R t < R
280 279 3impd R + t R < t t < R t < R
281 274 280 sylbid R + t R R t < R
282 281 imp R + t R R t < R
283 268 270 282 ltled R + t R R t R
284 283 112 syl R + t R R vol if t R R 2 t 2 R 2 t 2 = vol R 2 t 2 R 2 t 2
285 269 resqcld R + R 2
286 285 recnd R + R 2
287 286 adantr R + t R 2
288 191 adantl R + t t 2
289 287 288 subcld R + t R 2 t 2
290 289 sqrtcld R + t R 2 t 2
291 290 290 subnegd R + t R 2 t 2 R 2 t 2 = R 2 t 2 + R 2 t 2
292 157 291 sylan2 R + t R R R 2 t 2 R 2 t 2 = R 2 t 2 + R 2 t 2
293 285 adantr R + t R 2
294 8 adantl R + t t 2
295 293 294 resubcld R + t R 2 t 2
296 157 295 sylan2 R + t R R R 2 t 2
297 0red R + t R R 0
298 16 adantl R + t t
299 19 adantl R + t 0 t
300 rpge0 R + 0 R
301 300 adantr R + t 0 R
302 298 276 299 301 lt2sqd R + t t < R t 2 < R 2
303 12 adantl R + t t 2 = t 2
304 303 breq1d R + t t 2 < R 2 t 2 < R 2
305 302 277 304 3bitr3rd R + t t 2 < R 2 R < t t < R
306 294 293 posdifd R + t t 2 < R 2 0 < R 2 t 2
307 305 306 bitr3d R + t R < t t < R 0 < R 2 t 2
308 307 biimpd R + t R < t t < R 0 < R 2 t 2
309 308 exp4b R + t R < t t < R 0 < R 2 t 2
310 309 3impd R + t R < t t < R 0 < R 2 t 2
311 274 310 sylbid R + t R R 0 < R 2 t 2
312 311 imp R + t R R 0 < R 2 t 2
313 297 296 312 ltled R + t R R 0 R 2 t 2
314 296 313 resqrtcld R + t R R R 2 t 2
315 314 renegcld R + t R R R 2 t 2
316 315 314 28 syl2anc R + t R R R 2 t 2 R 2 t 2 dom vol
317 316 30 syl R + t R R vol R 2 t 2 R 2 t 2 = vol * R 2 t 2 R 2 t 2
318 296 313 sqrtge0d R + t R R 0 R 2 t 2
319 314 314 318 318 addge0d R + t R R 0 R 2 t 2 + R 2 t 2
320 292 breq2d R + t R R 0 R 2 t 2 R 2 t 2 0 R 2 t 2 + R 2 t 2
321 314 315 subge0d R + t R R 0 R 2 t 2 R 2 t 2 R 2 t 2 R 2 t 2
322 320 321 bitr3d R + t R R 0 R 2 t 2 + R 2 t 2 R 2 t 2 R 2 t 2
323 319 322 mpbid R + t R R R 2 t 2 R 2 t 2
324 315 314 323 47 syl3anc R + t R R vol * R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
325 317 324 eqtrd R + t R R vol R 2 t 2 R 2 t 2 = R 2 t 2 R 2 t 2
326 ax-resscn
327 326 a1i R +
328 271 269 78 syl2anc R + R R
329 rpcn R + R
330 329 sqcld R + R 2
331 330 adantr R + u R R R 2
332 328 sselda R + u R R u
333 332 recnd R + u R R u
334 329 adantr R + u R R R
335 rpne0 R + R 0
336 335 adantr R + u R R R 0
337 333 334 336 divcld R + u R R u R
338 asincl u R arcsin u R
339 337 338 syl R + u R R arcsin u R
340 1cnd R + u R R 1
341 337 sqcld R + u R R u R 2
342 340 341 subcld R + u R R 1 u R 2
343 342 sqrtcld R + u R R 1 u R 2
344 337 343 mulcld R + u R R u R 1 u R 2
345 339 344 addcld R + u R R arcsin u R + u R 1 u R 2
346 331 345 mulcld R + u R R R 2 arcsin u R + u R 1 u R 2
347 eqid TopOpen fld = TopOpen fld
348 347 tgioo2 topGen ran . = TopOpen fld 𝑡
349 iccntr R R int topGen ran . R R = R R
350 271 269 349 syl2anc R + int topGen ran . R R = R R
351 327 328 346 348 347 350 dvmptntr R + du R R R 2 arcsin u R + u R 1 u R 2 d u = du R R R 2 arcsin u R + u R 1 u R 2 d u
352 areacirclem1 R + du R R R 2 arcsin u R + u R 1 u R 2 d u = u R R 2 R 2 u 2
353 351 352 eqtrd R + du R R R 2 arcsin u R + u R 1 u R 2 d u = u R R 2 R 2 u 2
354 353 adantr R + t R R du R R R 2 arcsin u R + u R 1 u R 2 d u = u R R 2 R 2 u 2
355 oveq1 u = t u 2 = t 2
356 355 oveq2d u = t R 2 u 2 = R 2 t 2
357 356 fveq2d u = t R 2 u 2 = R 2 t 2
358 357 oveq2d u = t 2 R 2 u 2 = 2 R 2 t 2
359 358 adantl R + t R R u = t 2 R 2 u 2 = 2 R 2 t 2
360 simpr R + t R R t R R
361 ovexd R + t R R 2 R 2 t 2 V
362 354 359 360 361 fvmptd R + t R R du R R R 2 arcsin u R + u R 1 u R 2 d u t = 2 R 2 t 2
363 157 290 sylan2 R + t R R R 2 t 2
364 363 2timesd R + t R R 2 R 2 t 2 = R 2 t 2 + R 2 t 2
365 362 364 eqtrd R + t R R du R R R 2 arcsin u R + u R 1 u R 2 d u t = R 2 t 2 + R 2 t 2
366 292 325 365 3eqtr4rd R + t R R du R R R 2 arcsin u R + u R 1 u R 2 d u t = vol R 2 t 2 R 2 t 2
367 284 366 eqtr4d R + t R R vol if t R R 2 t 2 R 2 t 2 = du R R R 2 arcsin u R + u R 1 u R 2 d u t
368 367 itgeq2dv R + R R vol if t R R 2 t 2 R 2 t 2 dt = R R du R R R 2 arcsin u R + u R 1 u R 2 d u t dt
369 269 269 300 300 addge0d R + 0 R + R
370 329 329 subnegd R + R R = R + R
371 370 breq2d R + 0 R R 0 R + R
372 269 271 subge0d R + 0 R R R R
373 371 372 bitr3d R + 0 R + R R R
374 369 373 mpbid R + R R
375 2cn 2
376 162 326 sstri R R
377 ssid
378 375 376 377 3pm3.2i 2 R R
379 cncfmptc 2 R R u R R 2 : R R cn
380 378 379 mp1i R + u R R 2 : R R cn
381 ioossicc R R R R
382 resmpt R R R R u R R R 2 u 2 R R = u R R R 2 u 2
383 381 382 ax-mp u R R R 2 u 2 R R = u R R R 2 u 2
384 areacirclem2 R 0 R u R R R 2 u 2 : R R cn
385 269 300 384 syl2anc R + u R R R 2 u 2 : R R cn
386 rescncf R R R R u R R R 2 u 2 : R R cn u R R R 2 u 2 R R : R R cn
387 381 385 386 mpsyl R + u R R R 2 u 2 R R : R R cn
388 383 387 eqeltrrid R + u R R R 2 u 2 : R R cn
389 380 388 mulcncf R + u R R 2 R 2 u 2 : R R cn
390 353 389 eqeltrd R + du R R R 2 arcsin u R + u R 1 u R 2 d u : R R cn
391 381 a1i R 0 R R R R R
392 ioombl R R dom vol
393 392 a1i R 0 R R R dom vol
394 ovexd R 0 R u R R 2 R 2 u 2 V
395 areacirclem3 R 0 R u R R 2 R 2 u 2 𝐿 1
396 391 393 394 395 iblss R 0 R u R R 2 R 2 u 2 𝐿 1
397 269 300 396 syl2anc R + u R R 2 R 2 u 2 𝐿 1
398 353 397 eqeltrd R + du R R R 2 arcsin u R + u R 1 u R 2 d u 𝐿 1
399 areacirclem4 R + u R R R 2 arcsin u R + u R 1 u R 2 : R R cn
400 271 269 374 390 398 399 ftc2nc R + R R du R R R 2 arcsin u R + u R 1 u R 2 d u t dt = u R R R 2 arcsin u R + u R 1 u R 2 R u R R R 2 arcsin u R + u R 1 u R 2 R
401 eqidd R + u R R R 2 arcsin u R + u R 1 u R 2 = u R R R 2 arcsin u R + u R 1 u R 2
402 fvoveq1 u = R arcsin u R = arcsin R R
403 oveq1 u = R u R = R R
404 403 oveq1d u = R u R 2 = R R 2
405 404 oveq2d u = R 1 u R 2 = 1 R R 2
406 405 fveq2d u = R 1 u R 2 = 1 R R 2
407 403 406 oveq12d u = R u R 1 u R 2 = R R 1 R R 2
408 402 407 oveq12d u = R arcsin u R + u R 1 u R 2 = arcsin R R + R R 1 R R 2
409 408 oveq2d u = R R 2 arcsin u R + u R 1 u R 2 = R 2 arcsin R R + R R 1 R R 2
410 409 adantl R + u = R R 2 arcsin u R + u R 1 u R 2 = R 2 arcsin R R + R R 1 R R 2
411 ubicc2 R * R * R R R R R
412 272 273 374 411 syl3anc R + R R R
413 ovexd R + R 2 arcsin R R + R R 1 R R 2 V
414 401 410 412 413 fvmptd R + u R R R 2 arcsin u R + u R 1 u R 2 R = R 2 arcsin R R + R R 1 R R 2
415 329 335 dividd R + R R = 1
416 415 fveq2d R + arcsin R R = arcsin 1
417 asin1 arcsin 1 = π 2
418 416 417 eqtrdi R + arcsin R R = π 2
419 415 oveq1d R + R R 2 = 1 2
420 sq1 1 2 = 1
421 419 420 eqtrdi R + R R 2 = 1
422 421 oveq2d R + 1 R R 2 = 1 1
423 1cnd R + 1
424 423 subidd R + 1 1 = 0
425 422 424 eqtrd R + 1 R R 2 = 0
426 425 fveq2d R + 1 R R 2 = 0
427 426 195 eqtrdi R + 1 R R 2 = 0
428 427 oveq2d R + R R 1 R R 2 = R R 0
429 329 329 335 divcld R + R R
430 429 mul01d R + R R 0 = 0
431 428 430 eqtrd R + R R 1 R R 2 = 0
432 418 431 oveq12d R + arcsin R R + R R 1 R R 2 = π 2 + 0
433 2ne0 2 0
434 251 375 433 divcli π 2
435 434 a1i R + π 2
436 435 addid1d R + π 2 + 0 = π 2
437 432 436 eqtrd R + arcsin R R + R R 1 R R 2 = π 2
438 437 oveq2d R + R 2 arcsin R R + R R 1 R R 2 = R 2 π 2
439 414 438 eqtrd R + u R R R 2 arcsin u R + u R 1 u R 2 R = R 2 π 2
440 fvoveq1 u = R arcsin u R = arcsin R R
441 oveq1 u = R u R = R R
442 441 oveq1d u = R u R 2 = R R 2
443 442 oveq2d u = R 1 u R 2 = 1 R R 2
444 443 fveq2d u = R 1 u R 2 = 1 R R 2
445 441 444 oveq12d u = R u R 1 u R 2 = R R 1 R R 2
446 440 445 oveq12d u = R arcsin u R + u R 1 u R 2 = arcsin R R + R R 1 R R 2
447 446 adantl R + u = R arcsin u R + u R 1 u R 2 = arcsin R R + R R 1 R R 2
448 447 oveq2d R + u = R R 2 arcsin u R + u R 1 u R 2 = R 2 arcsin R R + R R 1 R R 2
449 lbicc2 R * R * R R R R R
450 272 273 374 449 syl3anc R + R R R
451 ovexd R + R 2 arcsin R R + R R 1 R R 2 V
452 401 448 450 451 fvmptd R + u R R R 2 arcsin u R + u R 1 u R 2 R = R 2 arcsin R R + R R 1 R R 2
453 329 329 335 divnegd R + R R = R R
454 415 negeqd R + R R = 1
455 453 454 eqtr3d R + R R = 1
456 455 fveq2d R + arcsin R R = arcsin 1
457 ax-1cn 1
458 asinneg 1 arcsin 1 = arcsin 1
459 457 458 ax-mp arcsin 1 = arcsin 1
460 417 negeqi arcsin 1 = π 2
461 459 460 eqtri arcsin 1 = π 2
462 456 461 eqtrdi R + arcsin R R = π 2
463 455 oveq1d R + R R 2 = 1 2
464 neg1sqe1 1 2 = 1
465 463 464 eqtrdi R + R R 2 = 1
466 465 oveq2d R + 1 R R 2 = 1 1
467 466 424 eqtrd R + 1 R R 2 = 0
468 467 fveq2d R + 1 R R 2 = 0
469 468 195 eqtrdi R + 1 R R 2 = 0
470 469 oveq2d R + R R 1 R R 2 = R R 0
471 271 recnd R + R
472 471 329 335 divcld R + R R
473 472 mul01d R + R R 0 = 0
474 470 473 eqtrd R + R R 1 R R 2 = 0
475 462 474 oveq12d R + arcsin R R + R R 1 R R 2 = - π 2 + 0
476 434 negcli π 2
477 476 a1i R + π 2
478 477 addid1d R + - π 2 + 0 = π 2
479 475 478 eqtrd R + arcsin R R + R R 1 R R 2 = π 2
480 479 oveq2d R + R 2 arcsin R R + R R 1 R R 2 = R 2 π 2
481 452 480 eqtrd R + u R R R 2 arcsin u R + u R 1 u R 2 R = R 2 π 2
482 439 481 oveq12d R + u R R R 2 arcsin u R + u R 1 u R 2 R u R R R 2 arcsin u R + u R 1 u R 2 R = R 2 π 2 R 2 π 2
483 434 434 subnegi π 2 π 2 = π 2 + π 2
484 pidiv2halves π 2 + π 2 = π
485 483 484 eqtri π 2 π 2 = π
486 485 a1i R + π 2 π 2 = π
487 486 oveq2d R + R 2 π 2 π 2 = R 2 π
488 330 435 477 subdid R + R 2 π 2 π 2 = R 2 π 2 R 2 π 2
489 251 a1i R + π
490 330 489 mulcomd R + R 2 π = π R 2
491 487 488 490 3eqtr3d R + R 2 π 2 R 2 π 2 = π R 2
492 482 491 eqtrd R + u R R R 2 arcsin u R + u R 1 u R 2 R u R R R 2 arcsin u R + u R 1 u R 2 R = π R 2
493 368 400 492 3eqtrd R + R R vol if t R R 2 t 2 R 2 t 2 dt = π R 2
494 266 493 syl R 0 R R 0 R R vol if t R R 2 t 2 R 2 t 2 dt = π R 2
495 259 494 pm2.61dane R 0 R R R vol if t R R 2 t 2 R 2 t 2 dt = π R 2
496 161 238 495 3eqtr3d R 0 R vol S t dt = π R 2
497 156 496 eqtrd R 0 R area S = π R 2