1 00:00:01,010 --> 00:00:04,520 Wamakelekile kwintetho echaza indlela yokusebenzisa i"quadratic equation". 2 00:00:04,520 --> 00:00:06,730 Ngoko ke i"quadratic equation". ivakala ngathi yinto 3 00:00:06,730 --> 00:00:07,810 enobunzima kakhulu. 4 00:00:07,810 --> 00:00:09,930 Kwaye xa uqala ukubona i"quadratic equation, ungathi 5 00:00:09,930 --> 00:00:11,590 kulungile, hayi ukuphela ivakala njengento 6 00:00:11,590 --> 00:00:13,110 enobunzima, kodwa yinto enzima. 7 00:00:13,110 --> 00:00:14,930 Kodwa ngethemba uakubona, njengokuba sisaqubekeka 8 00:00:14,930 --> 00:00:16,580 nentetho yethu, ukuba ayikhonzima ukuyisebenzisa. 9 00:00:16,580 --> 00:00:19,040 Kwaye kwintetho ezayo exesheni ndizakubonisa 10 00:00:19,040 --> 00:00:21,300 indlela eyakhiwe ngayo. 11 00:00:21,300 --> 00:00:24,810 Ngoko ke, jikelele, sowufundile ukwenza ucalu calulo 12 00:00:24,810 --> 00:00:25,810 kwiqondo lesibini lalonxaki. 13 00:00:25,810 --> 00:00:30,910 Ufundile ukuba, ukuba ndino, mandithi "x" ophinda-phindwe kabini thabatha 14 00:00:30,910 --> 00:00:40,340 "x" thabatha 6, ilingana no0. 15 00:00:40,340 --> 00:00:42,970 Ukuba bendinalenxaki. "x" ophinda-phindwe kabini thabatha "x" thabtha "x' ilingana 16 00:00:42,970 --> 00:00:48,720 no0, lanto ungayicalu calulala uthi "x" thabatha 3 kwaye 17 00:00:48,720 --> 00:00:52,210 "x" dibanisa 2 ilingana no0. 18 00:00:52,210 --> 00:00:54,955 Ngokucacileyo ithetha ukuba "x" thabatha 3 lingana no 0 okanye 19 00:00:54,955 --> 00:00:57,073 "x" dibanis 2 lingana no0. 20 00:00:57,073 --> 00:01:03,512 Ngoko ke "x" thabatha 3 lingana no0 okanye "x' dibanisa 2 lingana no0. 21 00:01:03,512 --> 00:01:08,500 Ngoko ke "x" lingana no 3 okanye no thabatha 2. 22 00:01:08,500 --> 00:01:17,980 Kwaye, xa siyizoba phantsi yalento izakuba, ukuba bendino 23 00:01:17,980 --> 00:01:26,150 msebenzi othile "f" ka "x" ulingana no "x" ophinda-phindwe kabnini thabatha "x' thabatha 6. 24 00:01:26,150 --> 00:01:28,760 Ngoko ke lomgca usembindini ngoka "f" ka "x". 25 00:01:28,760 --> 00:01:32,670 Ungaqhelana kakhulu nomgca osembindini we"y". 26 00:01:32,670 --> 00:01:34,780 kulenxaki inje, akukho nxaki khakhulu. 27 00:01:34,780 --> 00:01:36,270 Kwaye lomgca usembindini we "x". 28 00:01:36,270 --> 00:01:40,430 Kwaye ukuba bekuzakufuneka ndiyizobile lenxaki, "x' ophinda-phindwe kabini thabatha "x" 29 00:01:40,430 --> 00:01:42,380 thabatha 6, ingajongeka ngoluhlobo. 30 00:01:42,380 --> 00:01:50,130 Kancinci ngoluhlobo--lento ngu "f' ka "x" ulingana no thabatha 6. 31 00:01:50,130 --> 00:01:52,900 Kwaye umfanekiso ozotyiweyo angakhangeleka ngolu hlobo. 32 00:01:52,900 --> 00:01:57,150 Nyuka, izakuhlala inyuka ngokwalandlela. 33 00:02:00,030 --> 00:02:03,150 Kwaye ngoku iya kuthabatha 6, ngoba xa "x' elingana no0. 34 00:02:03,150 --> 00:02:05,110 'F" ka 'x" ulingana no thabatha 6. 35 00:02:05,110 --> 00:02:07,800 Ngoko ke ndiyayazi iyagqitha pha kulancam. 36 00:02:07,800 --> 00:02:11,520 kwaye ndiyayazi ukuba xa "f' ka 'x' elingana no0, ngoko ke 'f' ka 'x' lingana 37 00:02:11,520 --> 00:02:14,960 no 0 ngaphezu komgca osembindini ka 'x', akunjalo? 38 00:02:14,960 --> 00:02:16,600 Ngoba lento ngu1. 39 00:02:16,600 --> 00:02:17,870 lento ngu0. 40 00:02:17,870 --> 00:02:19,160 lento ngu thabatha 1. 41 00:02:19,160 --> 00:02:21,510 Ngoko ke lento ngu, xa 'f' ka 'x' elingana no0, ngaphezulu 42 00:02:21,510 --> 00:02:23,420 komgca osembindini ka 'x', akunjalo? 43 00:02:23,420 --> 00:02:29,210 Kwaye siyayazi ilingana no0 kula ncam 'x' lingana no 3 kwaye 44 00:02:29,210 --> 00:02:32,330 'x' lingana no thabatha 2. 45 00:02:32,330 --> 00:02:34,360 Yeyonanto isiyicombululeyo apha. 46 00:02:34,360 --> 00:02:36,440 Mhlawumbi xeshikweni besisenza inxaki yokucazulula khange 47 00:02:36,440 --> 00:02:38,940 siqwalasele ngokomzobo wethu into besiyenza. 48 00:02:38,940 --> 00:02:42,070 Kodwa ukuba sithi la 'f' ka 'x' ulingana nenaki ethile, sayi 49 00:02:42,070 --> 00:02:43,270 lungiselela lanto yalingana no0. 50 00:02:43,270 --> 00:02:44,820 Ngoko ke sithi lenxaki, kuphi apho 51 00:02:44,820 --> 00:02:48,220 ilingana no0? 52 00:02:48,220 --> 00:02:49,390 Xa kutheni ilingana no0? 53 00:02:49,390 --> 00:02:51,720 Kulungile, ilingana no0 kwincam, akunjalo/ 54 00:02:51,720 --> 00:02:55,360 Ngoba kulapho u'f' ka 'x' elingana no0. 55 00:02:55,360 --> 00:02:57,490 Kwaye kwangoko into besiyenza xa besisombulula lento ngoku 56 00:02:57,490 --> 00:03:01,970 cazulula ku, sibonile ukuba, iinxnye zika'x' ezenze u 'f' ka 'x' 57 00:03:01,970 --> 00:03:04,160 lingana no0, ngokucacileyo ngezi ncam zimbini. 58 00:03:04,160 --> 00:03:06,740 Kwaye, ngokwe sigama, ezi zibizwa 59 00:03:06,740 --> 00:03:09,860 ngamaqanda, okanye ingcambu, zika 'f' ka 'x'. 60 00:03:09,860 --> 00:03:12,470 Makhe siqwalase lanto kancinane. 61 00:03:14,810 --> 00:03:23,700 Ngoko ke , ukuba ndinento enje ngo'f' ka 'x' ulingana no'x' ophinda-phindwe kabini dibanisa 62 00:03:23,700 --> 00:03:29,550 '4x' dibanisa 4, kwaye ndibuze kuwe, aphi amaqanda okanye 63 00:03:29,550 --> 00:03:31,770 ingcambu zika 'f' ka'x'. 64 00:03:31,770 --> 00:03:33,970 Yinto enye nokuthi, kuphi apho u'f' ka 'x' 65 00:03:33,970 --> 00:03:36,300 adinana khona nomngca osembindini ka'x'. 66 00:03:36,300 --> 00:03:38,210 Kwaye badibana xa umgca osembindika ka'x' 'f' ka 'x' eli 67 00:03:38,210 --> 00:03:39,440 ngana no0, akunjalo? 68 00:03:39,440 --> 00:03:42,120 Ukuba uyacinga ngomzobo bendikhe ndawenza we'graph'. 69 00:03:42,120 --> 00:03:45,720 Ngoko ke, masithi ukuba u 'x' ulingana no 0, kwangoko 70 00:03:45,720 --> 00:03:51,860 singathi, 0 ulingana no'x' ophinda-phindwe kabini dibanisa '4x' dibanisa 4. 71 00:03:51,860 --> 00:03:53,940 Kwaye siyayazi, singazicalu calula, ngu 'x' 72 00:03:53,940 --> 00:03:57,080 dibanisa 2 phinda-phinda 'x' dibanisa 2. 73 00:03:57,080 --> 00:04:07,090 Kwaye siyayazi ukuba iyalingana no0 xa 'x' elingana no thabatha 2. 74 00:04:07,090 --> 00:04:10,170 'x' ulingana no thabatha 2. 75 00:04:13,940 --> 00:04:18,270 Kulungile, kancinci--'x' ulingana no thabatha 2. 76 00:04:18,270 --> 00:04:22,380 Ngoko ke ngoku, siyayazi singamfumana njani u0 xa eyona 77 00:04:22,380 --> 00:04:24,560 nxaki kulula ukuyicazulula. 78 00:04:24,560 --> 00:04:27,500 Kodwa masenze eyona nxaki apho inxaki yethu 79 00:04:27,500 --> 00:04:28,850 kungakho lula ukuyicazulula konke konke. 80 00:04:28,850 --> 00:04:32,120 Masithi sino 'f' ka 'x' ulingana nothabatha '10x' 81 00:04:39,750 --> 00:04:45,380 ophinda-phindiweyo kabini thabatha '9x' dibanisa 1. 82 00:04:45,380 --> 00:04:47,580 Kulungile, xa ndijonga lento, nokuba bendino kuyahlula ngo 10 bendino 83 00:04:47,580 --> 00:04:48,650 nokufumana amaqhezu apha. 84 00:04:48,650 --> 00:04:53,130 Kwaye kunzima ukuyicinga indlela yokucazulula lento i'quadratic' 85 00:04:53,130 --> 00:04:54,860 Kwaye yilonto ibizwa ngokuba yi"quadratic equation" okanye 86 00:04:54,860 --> 00:04:57,580 liqondo lesibini lamanani anezalathi ezinga phezu kwesithathu. 87 00:04:57,580 --> 00:04:59,600 Kodwa masiyicwangcise-- Ngoko ke sizama ukuyisombulula lento. 88 00:04:59,600 --> 00:05:02,420 Ngoba sifuna ukuyazi kuphi xa ilingana no0. 89 00:05:02,420 --> 00:05:07,130 Thaba '10x' ophonda-phindwe kabini thabatha '9x' dibanisa 1. 90 00:05:07,130 --> 00:05:09,090 Sifuna ukwazi ngawaphi lamanani asendaweni ka'x' enza lento 91 00:05:09,090 --> 00:05:11,260 ilingane no0. 92 00:05:11,260 --> 00:05:13,730 Kwaye apha singasebenzisa isixhobo esibizwa ngokuba yi"quadratic equation". 93 00:05:13,730 --> 00:05:15,625 Kwaye ngoku ndizakuninika enye kezinqabileyo kwizibalo 94 00:05:15,625 --> 00:05:18,030 kwaye ngumbono omhle ukuyigcina enqondweni. 95 00:05:18,030 --> 00:05:21,330 I"quadratic equation' ithi ingcambu ze"quadratic' 96 00:05:21,330 --> 00:05:24,810 ziyalingana--kwaye masithi i'quadratic equation' ngu 97 00:05:24,810 --> 00:05:31,900 'x' mophinda-phindwe kabini dibanisa 'bx' dibanisa 'c' lingana no0. 98 00:05:31,900 --> 00:05:35,790 Ngoko ke kulomzekelo, u'a' ngu thabatha 10. 99 00:05:35,790 --> 00:05:39,940 'b' ngu thabatha 9, kwaye 'c' ngu 1. 100 00:05:39,940 --> 00:05:48,040 Isichazi se"quadratic fomula' yi ngcambu ka 'x' ilingana no thabatha 'b' dibanisa okanye thabatha 101 00:05:48,040 --> 00:05:58,060 ingcambu ephinda-phindwa kabini ka'b' thabatha u 4 phinda-phinda 'a' phinda-phinda 'c', 102 00:05:58,060 --> 00:06:00,230 yonke lonto ngaphezu ko' 2a'. 103 00:06:00,230 --> 00:06:02,843 Ndiyayazi ukuba ijongenga nzima kodwa xa uyisebenzisa ngamandla, uzakubona 104 00:06:02,843 --> 00:06:04,400 ukuba ayikhombi kwaphela. 105 00:06:04,400 --> 00:06:07,720 Kwaye ngumbono omhle ukuyi bamba ngengqondo. 106 00:06:07,720 --> 00:06:10,730 Ngoko ke masibandakanye i"quadratic ewauation' apha kulenxaki 107 00:06:10,730 --> 00:06:12,670 sisandula ukuyibhala phantsi. 108 00:06:12,670 --> 00:06:15,260 Ngoko ke ndithi sandula ukuthi--kwaye jonga, kukho into ecaleni 109 00:06:15,260 --> 00:06:18,610 kuka 'x', akunjalo? 110 00:06:18,610 --> 00:06:20,300 'a' ngumlingani ka 'x' ophinda-phindiweyo. 111 00:06:20,300 --> 00:06:23,570 'b' ngumlingani ka 'x' kwaye u'c' akatshintshi. 112 00:06:23,570 --> 00:06:25,100 Ngoko ke masiyisebenzise kule nxaki. 113 00:06:25,100 --> 00:06:26,250 Ngubani u-'b'? 114 00:06:26,250 --> 00:06:28,700 Kulungile, 'b' ngu thabatha 9. 115 00:06:28,700 --> 00:06:29,970 Singabona apha. 116 00:06:29,970 --> 00:06:33,980 'b' nguthabatha 9, 'a' ngu thabatha 10. 117 00:06:33,980 --> 00:06:34,970 'c' ngu 1. 118 00:06:34,970 --> 00:06:36,090 Akunjalo? 119 00:06:36,090 --> 00:06:42,350 Ngoko ke ukuba u-'b' ngu thabatha 9--ngoko ke masithi, nguthabatha 9. 120 00:06:42,350 --> 00:06:49,260 Dibanisa okanye thabatha ingcambu kathabatha 9 ophinda-phindwe kabini. 121 00:06:49,260 --> 00:06:49,810 Kulungile, ngu 81. 122 00:06:49,810 --> 00:06:53,140 thabatha 4 phinda-phinda ngo 'a' 123 00:06:56,940 --> 00:06:59,760 'a' ngu thabatha 10. 124 00:06:59,760 --> 00:07:03,240 Thabatha 10 phinda-phinda 'c', ngokucacileyo ngu 1. 125 00:07:03,240 --> 00:07:05,110 Ndiyayazi lento ithesa, kodwa ngethemba uza 126 00:07:05,110 --> 00:07:06,470 kuyiqonda. 127 00:07:06,470 --> 00:07:09,560 kwaye yonke lonto ngaphezu ko2 umphinda-phinde ngo 'a'. 128 00:07:09,560 --> 00:07:14,050 Kulungile, 'a' ngu thabatha 10, ngoko ke 2 phinda-phinda 'a' ngu thabahta 20. 129 00:07:14,050 --> 00:07:14,990 Ngoko ke masiyicazulule lanto. 130 00:07:14,990 --> 00:07:19,410 Thabatha 10 phinda-phinda ngo thabatha 6, ngu dibanisa 9. 131 00:07:19,410 --> 00:07:26,460 Dibanisa okanye thabatha ingcambu ka 81. 132 00:07:26,460 --> 00:07:30,660 Sino thabatha 4 umphinda-phinda ngo thabatha 10. 133 00:07:30,660 --> 00:07:31,870 Lento ngu thabatha 10. 134 00:07:31,870 --> 00:07:33,280 Ndiyayazi ithesa kakhulu, ndiyaxolisa kakhulu 135 00:07:33,280 --> 00:07:34,380 ngalonto, phinda-phinda ngo 1. 136 00:07:34,380 --> 00:07:39,410 ngoko ke thabatha 4 uphinda-phinde ngo thabatha 10 ngu 40, onesichazi esingu dibanisa 40. 137 00:07:39,410 --> 00:07:41,040 Dibanisa 40. 138 00:07:41,040 --> 00:07:46,070 Kwaye kwangoko sinazo zonke phezu ko thabatha 20. 139 00:07:46,070 --> 00:07:48,300 Kulungile, 81 dibanisa 40 ngu 121. 140 00:07:48,300 --> 00:07:52,330 Ngoko ke lento ngu 9 dibanisa okanye thabatha ingcambu 141 00:07:52,330 --> 00:07:58,290 ka 121 phezu ko thabatha 20. 142 00:07:58,290 --> 00:08:01,620 Ingcambu ka 121 ngu 11. 143 00:08:01,620 --> 00:08:03,170 Ngoko ke ndizohamba apha. 144 00:08:03,170 --> 00:08:06,184 Ngethemba awuzose uyiphose indlela yalento ndiyenzayo. 145 00:08:06,184 --> 00:08:13,720 Ngoko ke lento ngu 9 dibanisa oakanye thabatha 11, ngaphezu ko thabatha 20. 146 00:08:13,720 --> 00:08:19,090 kwaye ngoko ke ukuba sithi 9 dibanisa 11 phezu ko thabatha 20, ngu 9 147 00:08:19,090 --> 00:08:22,540 dibanisa 11 ngu 20, ngoko ke lenti ngu 20 phezu ko thabatha 20. 148 00:08:22,540 --> 00:08:23,730 Ngoku cacileyo ulingana no thabatha 1. 149 00:08:23,730 --> 00:08:24,900 Ngoko ke yigcambu enye. 150 00:08:24,900 --> 00:08:28,260 Ngu 9 dibanisa--ngoba lento ngu dibanisa oaknye thabatha. 151 00:08:28,260 --> 00:08:33,790 Kwaye enye ingcambu izakuba ngu 9 thabatha 11 phezu ko thabatha 20. 152 00:08:33,790 --> 00:08:37,720 Ngokucacileyo ilingana no thabatha 2 phezu ko thabatha 20. 153 00:08:37,720 --> 00:08:40,700 ngokucacileyo ilingana no 1 phezu ko 10. 154 00:08:40,700 --> 00:08:42,690 ngoko ke ngenye ingcambu. 155 00:08:42,690 --> 00:08:48,950 Ngoko ke ukuba bekunokufuneka ziyizobe phantsi lenxaki, besizokubona ukuba 156 00:08:48,950 --> 00:08:52,640 ngokucacileyo idibana kumgca osembindini ka'x', 157 00:08:52,640 --> 00:08:57,770 Okanye 'f' ka 'x' ulingana no0 kwincam ka'x' elingana no thabatha 158 00:08:57,770 --> 00:09:01,690 1 kwaye 'x' ulingana no 1/10. 159 00:09:01,690 --> 00:09:04,080 Ndizakwenza imizekelo eminizni kwicandelo lesibini, ngoba ndi 160 00:09:04,080 --> 00:09:06,100 yacinga, ukuba nantoni na, ndingani bhidekisa 161 00:09:06,100 --> 00:09:08,120 ngalena yodwa. 162 00:09:08,120 --> 00:09:11,680 ngoko ke, ndizakunibona kwicandelo lesibini sisebenzisa 163 00:09:11,680 --> 00:09:12,150 "quadratic equation".