第二第三第
日七初月二十年未丁腐日
WAH KIU YAT PO
日六月,一审八六九一膺公
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文
地理科
劉玉領 。
D168英文中學會考試題預習專欄
墨科
LESSON
(ATHELISTICS (10)
KHAX
RATIOS OF ANGLES OF ANY MAGITUDE, SINE & COSINE FORMUL DE for
The figonometical ratios of any
angla, 0° at pt. P en defined as. Singu 7-ordinate of PPN
the sup, to the 2'm dagise (ie, spunten) - 700 COSES; such as AAS, ASA, and SSA can be solved by Sma laut,
A,
NOTE: An ambiguous case only exist m ssa, ag Ginn A,
bi baba tin A.
A≤10 an ambiguous case.
1968
ny, than keun mē
15,
'
that kanais C.
•. e' is known
COS & OF
ordinate of p
ON
fan Ba
2-ordinate off IN, cotton nordinate off. ON
THE
With cente, fired redkis OP, let a circle be describat then the x, y axes divide the chole into a quacrants of l. f. Po to be the positions of P in the four quadreals, as thom, then it will be soon bab Crates of is alway de regarded as positive for op only fixes the boundary of 03:
*guadrant ALL the values ar t'be,
Caly the x ordinate is I've. this in the 3oo quadrant: Only the Xxy ordinates are -
Only the ·odmate ta -
Cis In the lat
Riis In the 2" quadrant:
oh) In the 4th justrant
Hence, we find :
BASING
the fundamental formulae, such as
hots in all casts
tre hae for any * ).
EXAMPLE I: If ten A =- find Sin A and Cas A.
The boundary line of A, as shown, and the either in the
4* quadrant. ('wof
In eiher casa, the radius OP madis
From
quadrants vinh
There ar
Cas A have
from the above
ON change as the vacations the angle, result
EXAMPLE 4
ising in absolute value Creasing
ng the value of
1150) 3 IMA" SRC 186 + 3 càe 90′.
Na summary of
Example 4 The sides of a trangle am 12-15 and
and the included angle is coʻ, save the and find the arts of the triangle.
ZION Denote the a by ABC
By
Geography (10).
On the given sketch sap of Ceylon,
(1) Name the latitude and the longitude and the
(11) Insert the main railway lines in Ceylon
(111) Shade the central highlands of Ceylon
(iv) Print T over the best example where tea le
grown
Jaffna
Cosine formula,
Kannar
a2=b+c®- 2De Cas A
x (36477)(IL-13) can be
Trincomalee
sine formula,
(2)
EXAMPLE
SOLUTON
sine form
Colombo
Gallo
Batticaloa
matter of
(b) Explain the distribution of tea in Ceylon,
Tea requires warm and wet areas with woals drained soil on hilly slopes. Good drainage la essential for it cannot tolerate water standing. over tis roots. But a certain amount of frost is not injurious, it therefore can be grown at great elevations in tropical lands.
RIES
In Ceylon, temperature is high throughout the year in all parts of Ceylon but rainfall i8 not evenly distributed. The wettest parts aro the hilly slopes facing the summer on-shore S.k monsoon. Tea plantations are located mainly along the south-western slopes of the Central Highlands between Kandy and Nuwara Eliya at a level of 30001. But it may e extend right up to. s height of 7000. Ceylon's high-grown! well known in the world market for its quality. Thus, relief, climate, par rainfall, and soil all have parts to play the distribution of tea in Ceylon. write an essay on land utilisation in the northern lowland Dry Zone of Ceylon,
There is a large stretch of lowlana extending from the extreme north of Ceylon to its middle part. This is referred to as part of the Dry Zone for it, having nó mountains to intercept the moisture-laden winds, receives less than 50a of rainfall per year. The land is}
(未完轉入第三張第三页)
and
Sia 45
formala, area of the triangular field is
•Cos (r 2 =) GOS&
COS (T2×)= & WAK
dan(F£«)=ş
"PQ=&R, pton
006.7).
A
If the additional melakoni Sin 45 m a sin 28ES CONTES given, then the axpréstian becomes 1/0X/10, NOTE: By Subst, the sine formula, m=sme=un
the area formula becomes:
ae Din B
fogak sin A)(b sie (a) sin B
+b2 sin A bin C]
Asm C) as H
Fin
above example, we can dindly find
1328
HINT: & Aus
Exp. = 3(£)2+ 4(4)-401)-3(4)*+ ¿«)*
Each int
Each
the mere radiant az
rad.
length of the "harsa" sun
EXERCISE TO
Find the value of
615 fan Tr cos-
As shown in tig.
AD is a median of af85;
акрми
the fact proved m Example 3, to in terms of B, C) and avalu
& in the following caseri (a) B=35.",
A
any three parts triangle am
abore showed
(sme formula)
· Cas A. ( Cosinu "formula.
the triangle.
From Example 6 ( Lesson T Kudian measure of an angle
subtending are
4. The sides ef
2958*
PROOF
greatest angle is of the top k of a
that the The angle of ukvation mast from two pointi
its fact & wre
the height of me
B. on the sums tonlar 32°14' and sees map i maste 52 ft, and thus,
earings of A and B from H are 270° and 3407; chance AB anda the beating,
resp. find the
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