s'(r)=4pir+4pil
f'(x)=2x(7x-10x^2-1)-x^2(-20x+7)=14x^2-20x^3-2x+20x^3-7x^2=7x^2-2x
y'(t)=2t+(-)2/t^3
v'(h)=-6/h^3-2
v(a)=(3a-5)^2(4a^2-1)
v'(a)=2(4a^2-1)(3a-5)+(3a-5)^2*8a=(3a-5)(8a^2-2+8a(3a-5))
s'(r)=4pir+4pil
f'(x)=2x(7x-10x^2-1)-x^2(-20x+7)=14x^2-20x^3-2x+20x^3-7x^2=7x^2-2x
y'(t)=2t+(-)2/t^3
v'(h)=-6/h^3-2
v(a)=(3a-5)^2(4a^2-1)
v'(a)=2(4a^2-1)(3a-5)+(3a-5)^2*8a=(3a-5)(8a^2-2+8a(3a-5))