Originally Posted by

**MathTooHard**

Also, anyone know a way to evaluate line integrals on Mathematica?

Mathematica can do line integrals if you supply the parameterization:

Here's yours:

Code:

In[24]:=
x[t_] := Cos[t];
y[t_] := Sin[t];
Integrate[Sin[x[t]]*Derivative[1][x][t],
{t, 0, Pi}] + Integrate[
Cos[y[t]]*Derivative[1][y][t],
{t, 0, Pi}]
x[t_] := t;
y[t_] := -3*t - 3;
Integrate[Sin[x[t]]*Derivative[1][x][t],
{t, -1, -2}] + Integrate[
Cos[y[t]]*Derivative[1][y][t],
{t, -1, -2}]
Out[26]=
0
Out[29]=
Cos[1] - Cos[2] + Sin[3]