$$! A(3,1,2)% B(4,3,0) C(1,2,5)
14
10 2 3
10 3
26 2
114 2 1
* " !
4 tan tan
2 A+ B=
2 17 tan
3
tanA− B=− %
) 2
tan( A+B
9 13
−
9 11
−
1
−
9 7
−
9 5
−
+ , ! $ ! " & " ! α,β,β2 α β !#
! ! " ! ! 2x2+kx+6=0% " ! ! #
+
-+
)
-) -)
) )
. f(x)=3sinx+3cosx / " !0 (0,2π) 1 " 2
6
π
4
π
3
π
2
π
4 3π
) & !# ! ! " ! px2−(2p+1)x+2=0 mn=1
" ! ! !# ! ! " ! !
0 2 2 17
2x2+ x+ =
0 2 2 17
2x2− x+ =
& 4x2+17x+4=0
) 4x2−17x+4=0
) " ! !
125 52x+y+z =
7 1 73x−y+2z =
64 2x+2y−z =
(
3
= −z y
1
=
x
& 2x+y=3y+2z ) x+y+z=2
2 1 cos
sin cos tan
1 1
tan 2
=
b a
x x
x x
x
%
a
b=2 % 0≤x≤π
6
π
12
π
&
6 5π
)
12 5π
