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SOME VERY REMARKABLE
PROPOSITIONS FOR THE
solution of spherical triangles
with wonderful ease.
To solve a spherical triangle without dividing it
into two quadrantal or rectangular triangles.
Prop. 1.
Iven three sides, to find any angle.
And conversely,
Prop. 2.Given three angles, to find any side.
This is best done by the three methods explained in my work on Logarithms, Book II. chap. vi. sects. 8, 9, 10.
Prop. 3.
Given the side A D, & the angles D & B, to find the side A B.
Multiply the sine of A D by the sine of D; divide the product by the sine of B, and you will have the sine of A B,
4. Given
