View Compilation Error

0_0_19237895_29382.cpp:3:15: error: 't' was not declared in this scope
     double jc(t)
               ^
0_0_19237895_29382.cpp:4:5: error: expected ',' or ';' before '{' token
     {
     ^
0_0_19237895_29382.cpp: In function 'int main()':
0_0_19237895_29382.cpp:25:18: error: 'jc' cannot be used as a function
         x+=1/jc(i);
                  ^