1. Вычислите значения, воспользуйтесь 75 = 45 +30 , 15 =45 -30 а) sin75 б) tg15

а) sin75 = sin(45 + 30) = sin45cos30 + cos45sin30 = (√2/2 * √3/2) + (√2/2 * 1/2) = √6/4 + √2/4 = (√6 + √2) / 4

б) tg15 = sin15 / cos15 = sin(45 - 30) / cos(45 - 30) = (sin45cos30 - cos45sin30) / (cos45cos30 + sin45sin30) = (√2/2 * √3/2 - √2/2 * 1/2) / (√2/2 * √3/2 + √2/2 * 1/2) = (√6/4 - √2/4) / (√6/4 + √2/4) = (√6 - √2) / (√6 + √2)