Recent content by sssc

Thanks a lot.

Thanks a lot.

Homework Statement Do anyone know how to solve: y=LN x y=e+1-x Homework Equations y=LN x y=e+1-x The Attempt at a Solution LN x=e+1-x x=e^e * e^1 / e^x x*e^x=e^(e+1) then I don't know how to solve, must I solve it graphically? Actually, the original question is...

sorry, I think I typed it wrongly at first, it is x+y but not xy^2 for the density. Yes . I just do the integration but don't know why the answer is incorrect. Can anyone help me to check this? 2*∫ ∫ (x+y) dx dy where x: - (4-y^2)^0.5 -> (4-y^2)^0.5 y: 0 -> 2 =2*∫ [ ((x^2)/2+xy)] dy...

The question is here: A lamina covering the quarter circle x^2 + y^2 </= 4 ,x>0, y>0, has (area) density x+y. Find the mass of the lamina. Answer=16/3 But I change it to finding the whole circle I do it like this: cutting the circle into columns parallel to the x-axis ∫ ∫ (x+y) dx...

Homework Statement I would like to ask how to find the mass of a circle with equation x^2+y^2=4 given its density=xy^2 by not using polar coordinate but use dxdy or dydx ( cut the circle into pieces parallel to x-axis or y-axis ) Homework Equations x^2+y^2=4 xy^2 The...