We are required to find the cosine and tangent of 60°. Here we use an equilateral triangle whose side is 2 units, the height of the triangle by Pythagorean theorem will be √3 units, the base of the right angle triangle formed by bisection of the base will be 1 unit.
thus:
tan θ=opposite /adjacent
opposite= √3
adjacent=1
hence:
tan 60=√3/1=√3
cos θ=adjacent/ hypotenuse
adjacent=1
hypotenuse=2
thus
cos 60=1/2
