Page 27 - Module & More Matematik Tambahan Tg5
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Matematik Tambahan Tingkatan 5 Bab 1 Sukatan Membulat
(c) Panjang lengkok ADB = π(5) 4. Rajah menunjukkan satu semibulatan berpusat
Arc length ADB O dan berjejari 5.2 cm. EODB ialah satu sektor
π dengan keadaan sudut DEB = 0.7 rad dan
Panjang lengkok AEB = (10)
1 Arc length AEB 3 panjang lengkok DB ialah 5 cm.
The diagram shows a semicircle with centre O and
10 radius 5.2 cm. EODB is a sector such that angle DEB =
Perimeter = π + 5π
3 0.7 rad and the arc length DB is 5 cm.
BAB (d) Luas berlorek = Luas semibulatan – luas C
= 26.18 cm
tembereng D B
Shaded are = area of semicircle – area of segment
1 1 π 1
= π(5) − (10) 2 − (10) sin60° O
2
2
2 2 3 2
E
= 30.21 cm 2
A
3. Rajah menunjukkan satu cermin OPQR dan Cari/Find
bahagian berlorek ialah kayu hiasan yang (a) panjang EB,
terdiri daripada dua sektor sama, iaitu OPQR the length of EB,
yang berpusat O dan QPOR yang berpusat Q (b) perimeter dan luas rantau berlorek itu.
the perimeter and the area of the shaded region.
dengan jejari yang sama, j.
The diagram shows a mirror OPQR and the shaded (a) OC = 5.2 cm C
region is a decorative wood frame which is made up B
of two similar sectors, which is OPQR centred at O and DB = 5 cm D
QPOR centred at Q of the same radius, j. = 0.7DE O
P DE = 5 = 7.14 cm 0.7 rad
0.7 E
EB = 7.14 cm A
(b) Perimeter = π(5.2) + 7.14 + 5 + (10.4 − 7.14)
O Q
= 31.74 cm
Luas berlorek = Luas semibulatan – Luas
sektor
R Shaded area = Area of semicircle – Area of sector
2π 1 2 1 2
(a) Tunjukkan bahawa ∠POR = rad. = π(5.2) – (7.14) (0.7)
3 2 2
2π = 24.63 cm 2
Show that ∠POR = rad.
3
(b) Cari perimeter and luas kayu hiasan jika
jejari sektor ialah 0.5 m. 5. Rajah menunjukkan sebuah sektor BOA
Find the perimeter and the area of the decorative berpusat O. Diberi OC = CB = 4 cm.
wood if the radius of the sector is 0.5 m. The diagram shows a sector BOA with centre O. Given
that OC = CB = 4 cm.
(a) Oleh sebab/ since OP = PQ = OQ.
π P
Maka, Hence, ∠POQ = 60° = B
2π 3 = =
∠POR = rad O Q
3 π
(b) Panjang lengkok PQ = 0.5 = = 0.75 rad
Arc length PQ π 3 R
= cm O C A
6 π
Jumlah perimeter = 4(0.5) + 4 = 4.09 m
Total perimeter 6 Cari/Find
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