matem

[missa]

Molq wi hora reshete mi zad po matem sin2alpha-sin2beta 2 e na stepen molq wi imam kontrolna

[Chacho]

sin²a-sin²b = (sina-sinb)(sina+sinb) = [2sin((a+b)/2).cos((a-b)/2)].[2((a-b)/2).cos((a+b)/2)] = [2sin((a+b)/2).cos((a+b)/2)].[2(sin(a-b)/2).cos((a-b)/2)] = sin(a+b).sin(a-b)