(arctg√(x²+2x))'=[1/(1+x²+2x)](x²+2x)'=(2x+2)/(1+2x+x²)=2(x+1)/(x+1)²=
=2/(x+1)
(2⁻ˣctg(x/3))' u=2⁻ˣ u'=2⁻ˣ*ln2
v=ctg(x/3) v'=-1/[sin²(x/3)*1/3]=-3/sin²(x/3)
y'=(uv)'=u'v+v'u=2⁻ˣln2*ctg(x/3)-2⁻ˣ*3/sin²(x/3)
номер 3 повторяет номер 1
[x√(4-x²)]'+[4arcsin(x/2)]' u=x u'=1 v=√(4-x²) v'=1*(-2x)/2√(4-x²)
v'=-x/√(4-x²)
y'=u'v+v'u+4*0.5*1/√(1-x²/4)
y'=√(4-x²)-x²/√(4-x²)+2/√(4-x²)