Question

how to find ratios by geometrically
e.g. find cosec 30 and cos 60....
please reply fast....
if u know than give the answer......

Answer 1

for 60 and 30 degrees draw an equilateral triangle abc.
draw a perpendicular bisector ad. where d is a point on bc.
let all the equal sides be 2a
then as ad bisects bc,measure of bd will be a
then using pgt you will get ad as
$\sqrt{3} a$
using these measure u can take out the trigno. ratios.
(also angle bad will be equal to 30. as ad is also the angle bisector of angle a. all these are the properties of equilateral triangle)