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x gosc: Oblicz x
 24 
sin(4arctg(x)) =

 25 
6 sie 10:49
www: 1/2, 1/3, −2, −3
6 sie 10:59
Mariusz: sin(4α)=2sin(2α)cos(2α) sin(4α)=4sin(α)cos(α)(cos2(α)−sin2(α)) sin(4α)=4cos(α)sin(α)(1−2sin2(α)) sin(4α)=4cos(α)(sin(α)−2sin3(α)) sin(4α)=4(sin(α)cos(α)−2sin3(α)cos(α)) sin(4α)=4(sin(α)cos(α)−2sin2(α)(sin(α)cos(α))
 sin(α) 
tg(α)=

 cos(α) 
tg(α)cos(α)=sin(α) tg(α)cos2(α)=sin(α)cos(α)
 cos2(α) 
tg(α)

=sin(α)cos(α)
 cos2(α)+sin2(α) 
tg(α) 

=sin(α)cos(α)
1+tg2(α) 
 sin(α) 
tg(α)=

 cos(α) 
tg(α)cos(α)=sin(α) tg2(α)cos2(α)=sin2(α)
 cos2(α) 
tg2(α)

=sin2(α)
 cos2(α)+sin2(α) 
tg2(α) 

=sin2(α)
1+tg2(α) 
sin(4α)=4(sin(α)cos(α)−2sin2(α)(sin(α)cos(α))
 x 2x2 x 24 
4(


*

)=

 1+x2 1+x2 1+x2 25 
x 2x3 6 


=

1+x2 (1+x2)2 25 
x−x3 6 

=

(1+x2)2 25 
25x−25x3=6(1+2x2+x4) 6x4+25x3+12x2−25x+6=0 * 24 144x4+600x3+288x2−600x+144=0 (144x4+600x3)−(−288x2+600x−144)=0 (144x4+600x3+625x2)−(337x2+600x−144)=0 (12x2+25x)2−(337x2+600x−144)=0
 y y2 
(12x2+25x+

)2−((12y+337)x2+(25y+600)x+

−144)=0
 2 4 
 y2 
4(

−144)(12y+337)−(25y+600)2=0
 4 
(y2−576)(12y+337)−625(y+24)2=0 (y+24)(y−24)(12y+337)−625(y+24)2=0 (y+24)((y−24)(12y+337)−625(y+24))=0 y=−24
 y y2 
(12x2+25x+

)2−((12y+337)x2+(25y+600)x+

−144)=0
 2 4 
(12x2+25x−12)2−((−288+337)x2+0x+0)=0 (12x2+25x−12)2−49x2=0 (12x2+25x−12)2−(7x)2=0 ((12x2+25x−12)−7x)((12x2+25x−12)+7x)=0 (12x2+18x−12)(12x2+32x−12)=0 (2x2+3x−2)(3x2+8x−3)=0
 −3−9+4*2*2 
x1=

 2*2 
 −3+9+4*2*2 
x2=

 2*2 
 −8−64+4*3*3 
x3=

 2*3 
 −8+64+4*3*3 
x4=

 2*3 
x1=−2
 1 
x2=

 2 
x3=−3
 1 
x4=

 3 
6 sie 20:56