1)arcsin 0 =0
2)arccos 1= 0 ;
3)arcsin√2/2 =π/4 ;
4)arccos 3 не существует угол косинус которой =3 ;
5)arcsin (-1) = -π/2 ;
6)arccos(-√3/2) = π -π/6 = 5π/6 ;
7)arctg 0 = 0 ;
8)arctg 1 =π/4 ;
9)arctg(-√3) = - π/3 ;
10)arcctg(-√3/3) = π -π/3= 2π/3 ;
11)arcsin(-1/2)+arccos 1 = -π/6 +0 = -π/6 ;
12) (arcsin -1)/2+ arccos 1 = -π/4+0= -π/4;
13)cos ( arccos 1) =1;
14)sin(arcsin√2/2) =√2/2 ;
15)arcsin (sin π/4) =arcsin(√2/2) =π/4 ;
16)arccos ( cos(-π/4))=arccos ( cos(π/4))=arccos (√2/2))=π/4 ;
17)cos (arcsin(-1/3))=cos(arccos(√8/3)= √8/3 =2√2/3 ;
18)tg(arccos(-1/4)) =tq(arctq(-√15) = - √15; 1+tq²α= 1/cos²α
19)sin(arcctg(-2)) =sin(arcsin(1/√5)=1/√5 ;
20) arcsin(cos π/9) =arcsin(sin(π/2 - π/9))=arcsin(sin7π/18) =7π/18 .
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Объяснение:
-4х²-1,6х+0,09=0
4х²+1,6х-0,09=0
D=b²-4ac=1,6²+4*4*0,09=4
х₁=(-b-√D)/2a=(-1.6-2)/2*4=-3,6/8=-0.45
х₂=(-b+√D)/2a=(-1.6+2)/8=0.4/8=0.05
ответ: х₁= -0,45 х₂=0,05
2)0.1х²-14=-0,4х
0,1х²+0,4х-14=0
D=b²-4ac=0.4²+4*0,1*14=5,76
х₁=(-b-√D)/2a=(-0.4-2.4)/0.2=-14
x₂=(-b+√D)/2a=(-0.4+2.4)/0.2=10
ответ: х₁=-14 х₂=10