f`(x)=-2/sqrt(1-4x)
f`(x_(o))=f`(-6)=5
f(x_(o))=sqrt(1-4*(-6))=5
y-f(x_(o))=f`(x_(o))*(x-x_(o))
y-5=(-2/5)(x+6)
y=(-2/5)x+(13/5)
S=S_( Δ АВС) - S_(криволинейного треугольника АВК)=
=(1/2)*5*((13/5)-(-6))- ∫ ^(1/4)_(-6)sqrt(1-4x)dx=
=(5*12,5)/2-(-1/4)*(1-4x)^(3/2)/(3/2)|^(1/4)_(-6)=
=...