Алгебра 9 класс 42 задание - 1 пожалуйста
Объяснение:
Ответ: cosα=-0,2√21, sin2α=-0,16√21, cos2α=0,68.
Ответ: sinα=-0,8, ctgα=0,75, tg2α=-24/7.
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*(-0%2C6)%7D%7B(-0%2C6)%5E2-(-0%2C8)%5E2%7D%3D%5Cfrac%7B2*0%2C48%7D%7B0%2C36-0%2C64%7D%20%3D%5Cfrac%7B0%2C96%7D%7B-0%2C28%7D%3D%5C%5C%3D-%20%5Cfrac%7B24%7D%7B7%7D%20%3D-3%5Cfrac%7B3%7D%7B7%7D%5Capprox-3%2C43%20.)