Integral Calculus

Please help me answer

∫dx/cos(x)sin(x)

sir pwede paki exaplain saan galing values nung "y"? thanks po :)

please help me with this!!!
Im really having hard time getting this.
Region 1 is bounded by the x axis, the line x=1 and the curve y=x^2. Region 2 is bounded by the two curves y=x^2 and x=y^2. Region 3 is bounded by the y axis, the line y=1 and the curve x=y^2. Find the volume and centroid of the solid generated when the indicated region is revolved about the given line:
A. Region 1 is revolved about y axis
Region 1 is revolved about x axis
B. Region 2 is revolved about y axis
Region 2 is revolved about x axis

Find the volume and centroid of the solid generated using disc and shel methods,as the region bounded by the curve y^2=8x, the x axis and the latus rectun of the curve is revolved about:
A. The x axis
B. The y axis
C. The latus rectum

Please help po dito

Region 1 is bounded by the x axis, the line x=1 and the curve y=x^2.find the volume and centroid of the solid generated when the indicated region is revolved about y axis and revolved about x axis

A trough of length 6 ft has for its vertical cross section an isosceles trapezoid. The upper and lower base are 6 ft and 2 ft respectively and the altitude is 2 ft. If the trough is full of water, find the force on the slant side of the trough.

The moment of inertia bounded by y=x^3 , y=2x , X + y= 6, with respect to x=2 pa help po until Friday. Plus ask ko Lang po ang pinakakapakipakinabang na calculus book for integration applications. Thanks.

Centroid of the solid generated by the area Bounded by y=x, y=3x and X + Y= 8 about y axis