Ответы и объяснения

2014-02-25T13:31:41+00:00
1) y` =(cosx)`·sinx+cosx·(sinx)`=-sinx·sinx+cosx·cosx =-sin²x+cos²x = cos2x
y(-2π/3) =cos (2·(-2π/3))= cos(-4π/3) = cos(-(π+π/3))=-cosπ/3 = -1/2
2)(x²-4)·2√x =0
x²-4 =0 или x=0
x₁=-2
x₂ =2
x₃ = 0
3)f`(x)=(2-1/x)` = -x⁻² = -1/x²
f`(1) = -1