Geogebra/C3/Tangents-to-a-circle/Khasi

Time	Narration
00:00	Khublei iaphi baroh . Ngi pdiang sngewbha iaphi sha kane ka jinghikai halor ka Tangents to a circle in Geogebra.
00:06	Ha kaba kut jong kane ka jinghikai , phin lah ban draw/dro ia ki tangents sha ka circle, sngewthuh ia ki properties jong ki tangents.
00:17	Ngi tharai ba phi lah don katto katne ki jingtip shaphang kumno ka Geogebra ka treikam.
00:22	Lada em , na bynta ka jinghikai ba iadei , sngewbha leit ha ka website ka jong ngi http://spoken-tutorial.org.
00:27	Ban record ia kane ka jinghikai , Nga pyndonkam da ka Ubuntu Linux OS Version 11.10, Geogebra Version 3.2.47.0.
00:41	Ngin pyndonkam da ki Geogebra tools kiba harum : Tangents Perpendicular Bisector Intersect two Objects Compass Polygon & Circle with Center and Radius.
00:58	To ngin open/plie ia ka Geogebra window kaba thymmai.
01:01	Click ha Dash home >> Media Applications. Hapoh Type, jied Education bad GeoGebra.
01:13	To ngin batai ia ki tangent sha ka circle.
01:16	"Tangent is a line that touches a circle at only one point".
01:22	U point uba ktah la khot "point of tangency".
01:27	Na bynta kane ka jinghikai, Ngan pyndonkam da ka Grid layout ha jaka jong ka "Axes", Right click ha u drawing pad.
01:35	Uncheck ia ka Axes, bad jied Grid.
01:39	To ngin draw/dro ia ka tangent sha ka circle.
01:42	Nyngkong to ngin draw/dro ia ka circle.
01:45	Jied Circle with Center and Radius tool na u toolbar.
01:49	Mark ia u point A ha u drawing pad.
01:52	Ka dialogue box ka plie/open.
01:53	to ngin type ia u value 3 na bynta u radius, click OK.
01:58	Ka circle bad ka centre A bad u radius 3 cm la draw/dro.
02:04	to ngin pynkynriah ia u point A & peit ba ka circle ka don ia u radius uba ia kajuh.
02:09	Nion ha u New Pointtool. Mark ia u point B shabar jong ka circle.
02:15	Jied ia ka Segment between Two Points tool. Pyniasoh ia ki points A bad B. ia U segment AB la draw/dro.
02:25	Jied ia ka Perpendicular Bisector tool, nion ha ki points A & B. Ka Perpendicular bisector sha u segment AB la draw/dro.
02:37	U Segment AB bad ka perpendicular bisector ki ia kynduh ha u point. Nion ha ka Intersect Two Objects tool.
02:44	Mark ia ki point jong kiba ia kynduh kum u C. to ngin pynkynriah ia u B & peit kumno ka perpendicular bisector bad u point C pynkynriah ryngkat bad u point B.
02:59	Kumno ban pynshisha ba u C u dei u midpoint jong u AB?
03:02	Nion ha ka Distance tool. Nion ha ki points A , C, C ,B. Phin iohi ba u AC = CB ka pyni ba u C u dei u midpoint jong u AB.
03:20	Jied ia ka Compass tool na u tool bar, nion ha ki points C, B bad C sa shisien... ban pyndep ia ka figure/dur.
03:30	Artylli ki circles ki ia kynduh ha artylli ki points.
03:33	Nion ha ka Intersect Two Objects tool. Mark ia ki points jong ka jingiakynduh kum u D bad E.
03:42	Jied ia ka Segment between Two Points tool.
03:45	Pyniasoh ia ki points B, D bad B , E .
03:53	Ki Segments BD bad BE ki dei ki tangents sha ka circle c.
03:59	to ngin wad ia katto katne ki properties jong kine ki tangents sha ka circle.
04:05	Jied ia ka Segment between Two Points tool.
04:08	Pyniasoh ia ki points A, D bad A, E.
04:14	Hapoh ki triangles ADB bad ABE, segment AD= segment AE (radii jong ka circle 'c'). to ngin peit na ka Algebra View ba u segment AD= segment AE.
04:34	∠ADB= ∠BEA, angle jong ka semicircle jong ka circle d. to ngin thew ia ka angle.
04:48	Click ha ka Angle tool. Click ha ki points A, D, B bad B, E, A, angles ki ia ryngkat/equal.
05:03	U Segment AB u iadei lang ha baroh arliang ki triangles, namarkat ka △ADB '≅' (is congruent to )△ABE da ka SAS rule jong ka congruency.
05:20	Ka pyni ba ki : tangents BD bad BE ki ia ryngkat/equal!
05:26	Na ka Algebra View, ngi lah ban wad ba ka tangents BD bad BE ki ia ryngkat/ equal.
05:33	Sngewbha peit ba ka tangent barabor ki don ha ka right angles sha u radius jong ka circle ha kaba ka ktah/touch. to ngin pynkynriah ia u point B & peit kumno ba ki tangents ki khih ryngkat bad u point B.
05:50	to ngin save ia ka file mynta. Nion ha File>> Save As.
05:54	Ngan type ia ka file name kum ka Tangent-circle. Nion ha Save.
06:08	to ngin iathuh ia ka theorem.
06:11	"Angle between tangent and chord at the point of tangency is same as an inscribed angle subtended by the same chord". Angle DFB ba hapdeng tangent & chord = inscribed angle FCB jong ka chord BF.
06:34	to ngin pynshisha ia ka theorem.
06:38	to ngin open/plie ia ka Geogebra window kaba thymmai. Click ha File >> New. to ngin draw/dro ia ka circle.
06:48	Click ha ka Circle with Center through Point tool na u tool bar . Mark ia u point A kum ka centre bad click sa shisien ban ioh ia u B.
06:59	Jied ia ka New Point tool. Mark ia u pointC ha ka circumference bad D shabar jong ka circle.
07:06	Jied ia ka Tangents tool na u toolbar. Nion ha u point D bad ha ka circumference.
07:14	Artylli ki tangents ki lah draw/dro sha ka circle.
07:16	Ki Tangents ki ia kynduh ha artylli ki points ha ka circle.
07:20	Nion ha ka Intersect Two Objects tool. Mark ia ki points jong kiba iadei kum u E bad F.
07:28	to ngin draw/dro ia ka triangle. Nion ha ka Polygon tool.
07:31	Nion ha ki points B, C, F bad B sa shisien ban pyndep ia ka figure/dur.
07:41	Hapoh ka figure/dur, BF ka dei ka chord sha ka circle c.
07:45	∠FCB ka dei ka inscribed angle da ka chord sha ka circle c.
07:53	∠DFB ka dei ka angle hapdeng ka tangent bad ka chord sha ka circle c.
08:01	to ngin thew/measure ia ki angles, nion ha ka Angle tool, nion ha ki points D, F, B bad F, C, B.
08:14	Phin iohi ba ka ∠DFB = ∠FCB. to ngin pynkynriah ia u point D & peit ba ki tangents bad ki chords ki iaid ryngkat bad u point 'D'.
08:31	to ngin save ia ka file mynta. Nion ha File >> Save As.
08:36	Ngan type ia ka file name kum ka Tangent-angle. Nion ha Save. Bad da kane , ngi la poi sha kaba kut jong kane ka jinghikai.
08:50	to ngin batai lyngkot. Ha kane ka jinghikai, ngi lah dep pule ban pynshisha ia ka:
08:57	Artylli ki tangents kiba draw/dro na u external point ki ia ryngkat/equal
09:01	Ka Angle hapdeng ka tangent bad u radius jong ka circle u long 90^0.
09:07	Ka Angle hapdeng ka tangent bad ka chord ki ia ryngkat/equal sha ka inscribed angle subtended da ka chord.
09:14	Kum ka assignment, Nga kwah iaphi ban pynshisha:
09:17	"Angle between two tangents drawn to a circle is supplementary to the angle subtended by the line-segment joining the points of contact at the centre ".
09:30	Ban pynshisha: Draw/Dro ia ka circle. Draw/Dro ia ki tangents na u external point.
09:37	Mark ia ki points kiba iadei/contact jong ki tangents. Pyniasoh ia ka centre jong ka circle sha ki points kiba iadei/contact.
09:44	Measure/Thew ia ka angle ha ka centre, measure/thew ia ka angle hapdeng ki tangents.
09:49	Kaei ka sum jong ki artylli ki angles kiba halor? Pyniasoh ia ka centre bad ka external point.
09:55	Hato u line-segment u bisect ia ka angle ha ka centre? Hint – Pyndonkam da ka Angle Bisector tool.
10:05	Ka output ka dei ban long kumne.
10:08	Ka Sum jong ki angles ka dei 180^0. U line segment u bisects ia ka angle.
10:16	Peit ia ka video kaba lah ban ioh na kane ka url http://spoken-tutorial.org/
10:19	Ka batai lyngkot ia ka Spoken Tutorial project. Lada phimdon ia ka bandwidth kaba biang, phi lah ban download bad peit ia ka it.
10:27	Ka Spoken tutorial project team: ka pynlong ia ki workshops da kaba pyndonkam da ki spoken tutorials.
10:32	Ka ai certificates sha kito kiba pass ia ka online test.
10:35	Ia ki jingtip ba kham bniah , sngewbha thoh/write sha ka contact@spoken-tutorial.org.
10:42	Ka Spoken Tutorial Project ka dei ka bynta jong ka Talk to a teacher project.
10:47	La kyrshan ia ka da ka National Mission on Education lyngba ka ICT, MHRD, Government jong ka India.
10:54	Ia ki jingtip ba kham bniah halor kane ka mission ki don ha kane ka link [1].
10:59	Ia kane ka script la pynkylla da i Ribajanai Wankhar bad nga dei u Thawlad Miki .
11:04	Khublei shibun ba phi lah iasoh.

Contributors and Content Editors

PoojaMoolya, Ribajanai, Thaw