Let ∇f=−4xe−x2sin(y)i⃗ +2e−x2cos(y)j⃗ . find the change in f between (0,0) and (1,π/2) in two ways. (a) first, find the change by computing the line integral ∫c∇f⋅dr⃗ , where c is a curve connecting (0,0) and (1,π/2). the simplest curve is the line segment joining these points. parameterize it