Page 100 - Math Grade 11 (Basic)

PROEUS DARA

dsw q tthru -q tf:lQlS tanp- sinq = sin(p-q) '1
u ~p~q
sin(p-q) '1
tGffl'!:31rh:lu~hnli tf:lQlS cotp + cotq = sin(p + q) sh cot p - cot q = --:--'-'---:--''-'-
/) u sinpsinq sinpsinq

sin(p+q) sin(p+q)
tanp + tanq = , cotp + cotq =
cos pcosq sinpsinq
sin(p-q) sin(p- q)
tanp- tanq = , cotp- cotq = '1
cospcosq sinpsinq

.. 5o
. 105o
391tnUl.n sm + sm I = 2 . 105o +]5o cos 105o -15o -- 2sJ·n60ocos45o
"' 1
Sill
2 2
= 2xJ3xJ2 = J6 '1
2 2 2
"' 2
391tnUlll WHWHtltHlif:l rul I +cos a+ cos2a '1
1
I+ cosa + cos2a = 1 + cos2a + cosa = 2cos a + cosa = 2cosa( cosa + ~)
2
= 2cosa( cosa +cos~) = 4cosacos(~ +~)cos(~-~) '1

0 ' 0
ill'UTHHU 1 2(~ + cot2a) = cot~- tan~ '1
u sm 2 a 2 2

2
2
2( cos ~ sin ~)
2
2 (~ + cot 2 a) = 2 (_1_ + cos2a) = 2 ( 2cos a ) = 2cosa =
sm 2 a sin2a sin2a 2sinacosa sin a 2sin~cos~
2 2
2a 2a
cos sin
2 2
= = cot~- tan~ 'I
a a a a 2 2
sin -cos- sin-cos-
2 2 2 2
0 • 0
rutmti~U 2
u
"A ·s ·c 4
B
A
Sill + sm + sm = cos cos2cos C'1
2 2
r.,~no . A . B . C ,., . A+ B A- B . C C
.""'"' sm + sm + sm = Lsm--cos + 2 sm cos
2 2 2
A+B 1t c . A+B C
tthrnA+B+C=n ==> = --- '1 i:lmsg sm-- =cos-
2 2 u 2 2
A+B . C
cos--= sm- '1
2 2
C A-B A+B C
tf:lQlS sinA +sinE+ sinC = 2cos cos-- + 2cos cos
2 2 2
C( B C
A
A+ B)
= 2cos cos A B + cos-- = 4cos cos cos '1
2 2 2 2 2
A, B, c r:tl~nhU~tfilrul'!:3ru '1 mum mm
teo u u Ul '-'>
1
.A.B.C
cos A +cos B +cos = + sm sm2sm
1 4
C
2 2
95