Question

Integral of ydx+x2dy where C=C1+C2.
C1 is the path of the straight line segment from the origin, (0,0) to the point (4,28).
C2 is the path of the parabola y=−x^2+10x+4 from the point (4,28) to the point (7,25) .

Answer 1

For C1, I have x=4t, dx=4 dt and y=28t, dy=28 dt

So the integral is from 0 to 4: (4t*28)+(28*16t^2) dt

For C2, I have x=t, y=-t^2+10t+4 giving dx=dt and dy=-2t+10

So the integral is from 4 to 7: -2t^3+9t^2+10t+4

C1=10453.3 and C2=-58.5 giving C=C1+C2= 10453.3-58.5=10394.8

This is wrong though. Can someone explain what I did wrong?

Answer 2

@Luigi0210

Answer 3

Too advanced for me xD
@whpalmer4 @ganeshie8 @mathmale

Answer 4

Thanks for the help tags luigi