Odpowiedzi

2010-02-18T23:14:29+01:00
Cos α = - 11/15 i α ∈ (π/2 ; π) to
sin α = √( 1 -( -11/15)² = √1 -(121/225) = √(225/225)-(121/225) =
= √ (104/225) = √4*26 /√225 = 2√26/ 15 ≈ 0,6798
Odp. b)