Z=(-1)²⁵(cos(π/15)+isin(π/15))²⁵=-(cos(25π/15)+isin(25π/15))=-cos(5π/3)-isin(5π/3)=-cos(2π-π/3)-isin(2π-π/3)=-cos(-π/3)-isin(-π/3)=
-cos(π/3)+isin(π/3)=-1/2+i√3/2
(sin56cos79+sin79cos56)/(cos66cos44-sin66sin44)=
=sin(56+79)/cos(66+44)=cos135/cos110=sin45/(-cos20)<0
(sin37+cos37)/(1-cos74+sin74)=(sin37+sin53)/(1-(cos74-cos16))=
=2sin90cos8/(1+2sin90sin24)=(2cos8/(1+2sin24)>0
(sin56cos79+sin79cos56)/(cos66cos44-sin66sin44) <(2cos8/(1+2sin24)
1) y=tg 4x
y ' = <u> 4 </u>
cos² 4x
y ' (-π/4) = <u> 4 </u> = <u> 4 </u> = 4/1 = 4
cos² (-4π/4) cos²(-π)
2) y=x³ -6x²+9x-11
y ' = 3x² -12x +9
3x²-12x+9=0
x²-4x+3=0
D=16-12=4
x₁=<u>4-2 </u>= 1
2
x₂=<u>4+2 </u>= 3
2
Ответ: 1 и 3.
(2^(2/3) *а^(2/3) *а^(1/2) *b^(1/2))/(a*b^(1/3)*2^(1/2) = 2^(1/6) *а^(1/6)*b^(1/6)= √2аb - здесь корень шестой степени