- 1. CIRCULARMEASURE ARCLENGTHSECTORAREA
Bytheendofthelessonyoushouldbeableto:
1.Convertdegreesintoradiansandviceversa.
2.Recognizepartsofacircleanduseappropriateterminology.
3.Usepriorknowledgeonlengthofcircumferenceandareaofcircleto
deduceformulaetocalculatearclengthandsectorarea.
4.Usepriorknowledgeonthetrigonometricformulafortheareaofa
triangletodeduceawaytocalculatetheareaofasegment.
5.Solveproblemsinvolvingarclength,sectorareaandareaofa
segment.
2. The unit circle 3. 2rad=360o rad=.... rad=......
.......rad=270o 4. Expressinradians 45o 60o 30o
Toconvertdegreestoradians,multiplyby 5.
Toconvertradianstodegrees,multiplyby Expressindegrees: 6.
Fillintheblanksinthefollowingtable 7.
Oneradianisdefinedasthesizeofangle
correspondingtoanarcoflength1unitina circleofradius1unit. 1unit
=1radian 8. diameter A B O C D E O P Q radius minorsector chord
minorsegment majorarc 9. CalculatethelengthoftheminorarcAB: A B
Arclength=2 rx 360 Arclength=2 rx 2 in degrees: in radians:
Arclength =r 10. CalculatetheareaoftheminorsectorAOB: A B in
degrees: in radians: SectorArea =r2 Sectorarea= r2 x 360
Sectorarea= r2 x 2 11. Reminder: A B C a b c
Areaoftriangle=xproductanytwosidesxsin(includedangle)
Areaofatriangle Areaoftriangle=absinC 12. 30 22 12cm 5cm Calculate
the area of the triangle: Areatriangle=15cm2 13. How can we
calculate the area of the minor segment?
Areasegment=AreasectorAOBAreatriangleAOB Areasegment= Areasegment=
A O B 14. How can we calculate the area of the major segment?
Areasegment=AreasectorAOB+AreatriangleAOB Areasegment= Areasegment=
A O B 15. Atendoflesson... TerminologyQuiz Seenextpage... 16.
1)Thedistancearoundtheedgeofacircle. Circumference
2)Thecircumferenceofanycircledividedbyitsdiameter. Pi
3)Aportionofthecircumferenceofacircle. Arc
4)Astraightlinethatlinkstwopointsonacircumference. Chord
5)Alinefromthecenterofacircletoapointonthecircle. Radius
6)Giventwopointsonacircumference,theshortestarclinkingthem.
Minorarc 7)Thedistancealongthecurvedlinemakingupthearc. Arclength
8)Theareaenclosedbytworadiiofacircleandtheirinterceptedarc.
Apieshapedpartofacircle. Sector
9)Theregionbetweenachordofacircleanditsassociatedarc. Segment 17.
Attachments ArclengthandSectorareaPastpapersProblems.rtf