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Mathematical formula FF
This is the second kind of surface integral, which is expressed by the surface expression Z =- root (R 2-χ 2-γ 2).

The third component of the normal vector is-1, and hutcheson d is x 2+y 2.

Origin = double integral _ (d) x 2 * y 2 * (root (r 2-x 2-y 2)) * (-1) dxdy.

Note that the last formula-1 is due to low demand.

Polar coordinates X = rcosa, Y = rsina Jacobian is r,

= integral (from 0 to R) doctor integral (from 0 to 2pi music) r 4 * cos 2a * sin 2a root (r 2-r 2) RDA

On the indivisible whole (music from 0 to 2pi) (1 cos4a)/ 8 =π/ 4.

Integral of variable substitution = Sina, 0

Integral (from 0 to π/ 2) sin 5a * cos 2ada

=1/3-2/5+1/7 = 8/105, finally.

= 2pi/ 105 .