Barrow, Isaac, Lectiones opticae & geometricae : in quibus phaenomenon opticorum genuinae rationes investigantur, ac exponuntur: et generalia curvarum linearum symptomata declarantur

Page concordance

< >
Scan Original
191
192
193
194
195 2
196 3
197 4
198 5
199 6
200 7
201 8
202 9
203 10
204 11
205 12
206 13
207 14
208 15
209 16
210 17
211 18
212 19
213 20
214 21
215 22
216 23
217 24
218 25
219 26
220 27
< >
page |< < (55) of 393 > >|
    <echo version="1.0RC">
      <text xml:lang="la" type="free">
        <div xml:id="echoid-div222" type="section" level="1" n="31">
          <p>
            <s xml:id="echoid-s10466" xml:space="preserve">
              <pb o="55" file="0233" n="248" rhead=""/>
            item PO ad TE parallela. </s>
            <s xml:id="echoid-s10467" xml:space="preserve">Eſtque EFq = EOq (CPq) + OFq
              <lb/>
            + 2 EO x OF (+ 2 CP x OF). </s>
            <s xml:id="echoid-s10468" xml:space="preserve">Verùm ob CP. </s>
            <s xml:id="echoid-s10469" xml:space="preserve">CA :</s>
            <s xml:id="echoid-s10470" xml:space="preserve">: OP.
              <lb/>
            </s>
            <s xml:id="echoid-s10471" xml:space="preserve">OF :</s>
            <s xml:id="echoid-s10472" xml:space="preserve">: CE. </s>
            <s xml:id="echoid-s10473" xml:space="preserve">OF; </s>
            <s xml:id="echoid-s10474" xml:space="preserve">eſt CP x OF = CA x CE; </s>
            <s xml:id="echoid-s10475" xml:space="preserve">ergò EFq =
              <lb/>
            CPq + OFq + 2 CA x CE. </s>
            <s xml:id="echoid-s10476" xml:space="preserve">item eſt AEq = CEq +
              <lb/>
            CAq - 2 CA x CE; </s>
            <s xml:id="echoid-s10477" xml:space="preserve">quapropter eſt EFq + AEq = CPq +
              <lb/>
            CAq + OFq + CEq. </s>
            <s xml:id="echoid-s10478" xml:space="preserve">hoc eſt EGq = (APq + PFq = )
              <lb/>
            CVq + PFq. </s>
            <s xml:id="echoid-s10479" xml:space="preserve">vel EGq - PFq = CVq. </s>
            <s xml:id="echoid-s10480" xml:space="preserve">Verùm eſt CE. </s>
            <s xml:id="echoid-s10481" xml:space="preserve">
              <lb/>
            (PO). </s>
            <s xml:id="echoid-s10482" xml:space="preserve">PF :</s>
            <s xml:id="echoid-s10483" xml:space="preserve">: CP.</s>
            <s xml:id="echoid-s10484" xml:space="preserve">AP :</s>
            <s xml:id="echoid-s10485" xml:space="preserve">: CP.</s>
            <s xml:id="echoid-s10486" xml:space="preserve">CV; </s>
            <s xml:id="echoid-s10487" xml:space="preserve">unde EGq - {CVq/CPq} CEq
              <lb/>
            = CVq; </s>
            <s xml:id="echoid-s10488" xml:space="preserve">adeóque linea GVG eſt _hyperbola_, cujus centrum C; </s>
            <s xml:id="echoid-s10489" xml:space="preserve">ſe-
              <lb/>
            miaxes CV, CP.</s>
            <s xml:id="echoid-s10490" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10491" xml:space="preserve">Not. </s>
            <s xml:id="echoid-s10492" xml:space="preserve">Ductà rectâ FQ ad TH perpendiculari, ſumptáque QR =
              <lb/>
            AE; </s>
            <s xml:id="echoid-s10493" xml:space="preserve">& </s>
            <s xml:id="echoid-s10494" xml:space="preserve">connexâ GR; </s>
            <s xml:id="echoid-s10495" xml:space="preserve">erit GR _hyperbolæ_ VGG perpendicularis;
              <lb/>
            </s>
            <s xml:id="echoid-s10496" xml:space="preserve">mihi præſta sîs ſidem; </s>
            <s xml:id="echoid-s10497" xml:space="preserve">aut ipſe rem ad Calculum exige; </s>
            <s xml:id="echoid-s10498" xml:space="preserve">eò verba
              <lb/>
            non proſundam.</s>
            <s xml:id="echoid-s10499" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10500" xml:space="preserve">XXVI. </s>
            <s xml:id="echoid-s10501" xml:space="preserve">Poſitione datæ ſint rectæ AC, BD (ſe interſecantes in X)
              <lb/>
              <note position="right" xlink:label="note-0233-01" xlink:href="note-0233-01a" xml:space="preserve">Fig. 59.</note>
            qnas decuſſet recta A B; </s>
            <s xml:id="echoid-s10502" xml:space="preserve">tum ductâ utcunque rectâ PKL ad AB
              <lb/>
            parallelâ, (quæ rectas AC, BD ſecet punctis P, K) ſit PL æqua-
              <lb/>
            lis ipſi BK; </s>
            <s xml:id="echoid-s10503" xml:space="preserve">erit linea ALL recta.</s>
            <s xml:id="echoid-s10504" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10505" xml:space="preserve">Nam, (ductâ XQ ad BA parallelâ, eſt AQ. </s>
            <s xml:id="echoid-s10506" xml:space="preserve">AP :</s>
            <s xml:id="echoid-s10507" xml:space="preserve">: (BX.
              <lb/>
            </s>
            <s xml:id="echoid-s10508" xml:space="preserve">BK :</s>
            <s xml:id="echoid-s10509" xml:space="preserve">: ) QX. </s>
            <s xml:id="echoid-s10510" xml:space="preserve">PL: </s>
            <s xml:id="echoid-s10511" xml:space="preserve">ergo linea ALL eſt recta.</s>
            <s xml:id="echoid-s10512" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10513" xml:space="preserve">XXVII. </s>
            <s xml:id="echoid-s10514" xml:space="preserve">Poſitione data ſit recta A X, & </s>
            <s xml:id="echoid-s10515" xml:space="preserve">punctum D; </s>
            <s xml:id="echoid-s10516" xml:space="preserve">neque non
              <lb/>
            linea DNN talis; </s>
            <s xml:id="echoid-s10517" xml:space="preserve">ut per D ductâ quâcunque rectâ MN (quæ re-
              <lb/>
              <note position="right" xlink:label="note-0233-02" xlink:href="note-0233-02a" xml:space="preserve">Fig. 60.</note>
            ctam AX ſecet in M, & </s>
            <s xml:id="echoid-s10518" xml:space="preserve">lineam DNN in N) ſit perpetim rectangu-
              <lb/>
            lum ex DM, DN æquale dato (puta quadrato ex Z); </s>
            <s xml:id="echoid-s10519" xml:space="preserve">erit linea
              <lb/>
            DNN circularis.</s>
            <s xml:id="echoid-s10520" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10521" xml:space="preserve">Nam ducatur DB ad AX perpendicularis; </s>
            <s xml:id="echoid-s10522" xml:space="preserve">ſitque DB. </s>
            <s xml:id="echoid-s10523" xml:space="preserve">Z :</s>
            <s xml:id="echoid-s10524" xml:space="preserve">: Z.
              <lb/>
            </s>
            <s xml:id="echoid-s10525" xml:space="preserve">DE; </s>
            <s xml:id="echoid-s10526" xml:space="preserve">& </s>
            <s xml:id="echoid-s10527" xml:space="preserve">connectatur NE; </s>
            <s xml:id="echoid-s10528" xml:space="preserve">Eſt jam DM x DN = Zq = DB x
              <lb/>
            DE; </s>
            <s xml:id="echoid-s10529" xml:space="preserve">quare DM. </s>
            <s xml:id="echoid-s10530" xml:space="preserve">DB :</s>
            <s xml:id="echoid-s10531" xml:space="preserve">: DE. </s>
            <s xml:id="echoid-s10532" xml:space="preserve">DN. </s>
            <s xml:id="echoid-s10533" xml:space="preserve">ergò triangula DBM, DNE
              <lb/>
            ſimilia ſunt; </s>
            <s xml:id="echoid-s10534" xml:space="preserve">quapropter angulus DNE rectus eſt; </s>
            <s xml:id="echoid-s10535" xml:space="preserve">itaque linea DNN
              <lb/>
            eſt circularis: </s>
            <s xml:id="echoid-s10536" xml:space="preserve">(ad circulum pertinens, _c@jus Diameter_ DE).</s>
            <s xml:id="echoid-s10537" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s10538" xml:space="preserve">Vides nedum rectam & </s>
            <s xml:id="echoid-s10539" xml:space="preserve">_hyperbolam_; </s>
            <s xml:id="echoid-s10540" xml:space="preserve">ſed & </s>
            <s xml:id="echoid-s10541" xml:space="preserve">ſuo modo rectam ac
              <lb/>
            _circulum_ ſibi lineas eſſe reciprocas. </s>
            <s xml:id="echoid-s10542" xml:space="preserve">Verùm hîc, etſi præludiis no-
              <lb/>
            ſtris nondum abſolutis, paulùm ſubſiſtamus.</s>
            <s xml:id="echoid-s10543" xml:space="preserve"/>
          </p>
        </div>
      </text>
    </echo>