Page 206 - Math Grade 11 (Advance)

PROEUS DARA

~fH@% x = lo?lcosa , cosa = _: = ~~

· 1 OP 1
6
y = I o?l cos f3 . cos f3 = I i'PI =
11

z = lo?l cosy , cosy = liPI = i
1

2
2
2
2. tHn mm cos a+ cos f3 +cos y =
IJ1 .,_,
-2
2
tfh ru cos a = TI , cos a = 4
121
9
6
36 ..
2
2
cos 13 = IT , cos 13 = ill a~ cosy = IT = cos y = 81
121
2 2 2 4 36 81 121 1
cos a+ cos f3 + cos y = +ill +ill = =
121 121
2 2 2
f::i 13 t @ g cos a + cos f3 + cos y = 1 '1
u

~m~H x = lo?lcosa , cosa = liPI = ~

y = lo?l cosf3 , cosf3 = liPI = ~

2 - =- ~
z = lo?lcosy , cosy = -
7
lo?l
2 2 2 4 9 36 49
2. cos a + cos f3 + cos y = - + - + - = - = 1
49 49 49 49
2 2 2
f::i 13 t @ g cos a + cos f3 + cos y = 1 '1
u

1 '1

.......
2
"""
2
2
2. Uw,mu, cos a+ cos f3+cos y 1 '1
IJ1 .,_,
201