Larson 6th edition gives the following solution; 

However, LineInt(VectorField(`<,>`(x, y)), Path(`<,>`(4*t, 3*t), t = 0 .. 1))

returns 25/2 and 

LineInt(VectorField(`<,>`(x, y)), Path(`<,>`(4*t, 3*t), t = 0 .. 1), output = integral)

returns

Int(25*t, t = 0 .. 1)

Why are the solutions different?

lineInt.mw

The physics package is pretty awesome, but one thing that would be a big help is some functionality for entering and resolving vectors in angle/magnitude format (50 angle 45 degrees, or what have you.) Is there a way to do this?

Thanks

Joe