2: f(x)=(9-x^2)/(x-3)=-(x+3)
Khi x<3 thì \(lim_{x->3^-}f\left(x\right)=-\left(3+3\right)=-6\)
\(lim_{x->3^+}f\left(x\right)=1-3=-2< >-6\)
=>f(x) bị gián đoạn tại x=3
1:
\(\dfrac{\sqrt{1+x}-1}{\sqrt[3]{1+x}-1}=\dfrac{1+x-1}{\sqrt{1+x}+1}:\dfrac{1+x-1}{\sqrt[3]{\left(1+x\right)^2}+\sqrt[3]{1+x}+1}\)
\(=\dfrac{\sqrt[3]{\left(x+1\right)^2}+\sqrt[3]{x+1}+1}{\sqrt{x+1}+1}\)
\(lim_{x->0^+}f\left(x\right)=\dfrac{\sqrt[3]{\left(0+1\right)^2}+\sqrt[3]{0+1}+1}{\sqrt{0+1}+1}=\dfrac{1+1+1}{1+1}=\dfrac{3}{2}=lim_{x->0^-}f\left(x\right)\)
=>Hàm số liên tục tại x=0


