Question

Am nevoie de ajutor la subiectul 3 exercițiul 2 b si c

Answer 1

2b) f(x)/x==(x²+9)/x=x+9/x
I=∫(x+9/x)dx=∫xdx+9∫dx/x=x²+9lnx x∈1[1,2]
Aplici  formula  Leibniz Newton
I=(x²/2+9*lnx)/1↑2=(2²/2+9ln2)-(1/2+9*ln1)=2+9ln2-1/2=3/2+9ln2
c)g(x)=x²+9-x²=9
Aplici  formula
V=π∫g²(x)dx=π∫9²dx=81π