sin(75)+cos(15) = sin(90-15)+cos(15) =
= cos(15) + cos(15) = 2cos(15) =
= 2cos(45-30) = 2cos45cos30 + 2sin45sin30 = 2•(√2/2)•(√3/2) + 2•(√2/2)•(1/2) = √6 / 2 + √2 / 2 =
= (√6+√2)/2
