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GANITASĀRASANGRAHA.
An example in illustration thereof. 22. In the case of an elliptical figure the shorter) diameter is 12, and the longer diameter is 36. What is the circumference and what is the resulting) arca (thereof) ?
The rule for arriving at the resulting) area of a conchiform curvilinear figuro:
23. In the case of a conobiform curvilinear figure, the measure of the (greatest) breadth diminished by half the measure of the mouth and multiplied by three gives the measure of the perimeter. One-third of the square of half (this) perimeter, increased by three-fourths of the square of half the measure of the mouth, (gives the area).
An example in illustration thereof.
21. In the case of a conchi-form figure the breadth is 18 hastax, and the moasure of the month thereof is 4 (hastax). You tell me what the perimeter is and what the caloulated area is.
The rule for arriving at the resulting) area of the concave and convex circular surfaces:
25. Understand that one-fourth of the circumference multiplied by the diameter gives rise to the calculated resulting) area. Thonoo, in the case of ooncave and convex areas like that of a
23. If a in the diametor and m in the measure of the month, then 3 (a - m) is the measure of the circumference; and (
41) and
* 3* *13) is tho moscuro of the aroa. The exact shape of the figore is not clear from the description given; but from the values given for the circumference and the Arda, it may bo conceived to consist of 3 unoquel semicircles placed so that their diameters ooincido in position as shown in figure 12, givon in the foot-note to abansa 6, in this chapter.
25. The area here specified soems to be that of the surface of the segment of a apliere ; and the messare of the area is stated to be, when symbolically represented, equal tox d, where c is the circumference of the sectional cirole, and d is the diameter thereof. But the area of the surface of a spherical megment of this kind is equal to 2 r., where is the radius of the sectional oirolo aud * is the height of the spherical segment.
