find the sin 60 degree?

60 is one of special angle that you need to remember the value of sin,cos at this angle.
sin(60)=(1/2) sqrt(3)

√3/2

sin(60°)
= (√3)/2

All angles of any equilateral triangle is 60 deg

If we drop a perpendicular from any vertex to the opposite side of a triangle, we would get a right angled triangle.

It can be proved geometrically that this perpendicular is also median by congruency of two triangles as the original triangle is equilateral.

Now, if we take the length of the side of original triangle as 'a', in the newly formed right angled triangle, base would be a/2

now in right angled triangle, perpedicular be p

So, by Pythagorus

a^2= p^2 + (a/2)^2
or, p^2 = a^2- (a/2)^2
= a^2- (a^2)/4
= 3(a^2)/4

p= sqrt(3)*a/2

sin(60)= p/hyp
=(sqrt(3)*a/2)/a
=sqrt(3)/2 Proved

Sin 60 Degrees

Square root of 3 over 2

you do it in your calculator

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