求分段函数新手入门恳请指点

用else if解决

#include < cmath >
#include < iostream >
#include < iomanip >
using namespace std;
int main()
{
double x,y;
cin>>x;
if(x>=0)
y=pow(x,0.5);
else
y=(x+1)(x+1)+2x+1/x;
cout<<setiosflags(ios::fixed)<<setprecision(2)<<y<<endl;
return 0;
}