36sin93гралуса/sin87градуса

Лебедев Дмитрий Сергеевич

Учитель математики

Проверено учителем

Для решения выражения 36sin93sin87the fraction with numerator 36 sine 93 raised to the composed with power and denominator sine 87 raised to the composed with power end-fraction воспользуемся формулами приведения тригонометрических функций.

  1. Преобразуем sin93sine 93 raised to the composed with power:
    Угол 9393 raised to the composed with power можно представить как (18087)open paren 180 raised to the composed with power minus 87 raised to the composed with power close paren или (90+3)open paren 90 raised to the composed with power plus 3 raised to the composed with power close paren. Удобнее использовать первый вариант, чтобы прийти к углу 8787 raised to the composed with power, который уже есть в знаменателе.
    Согласно формуле приведения sin(180α)=sinαsine open paren 180 raised to the composed with power minus alpha close paren equals sine alpha:
    sin93=sin(18087)=sin87sine 93 raised to the composed with power equals sine open paren 180 raised to the composed with power minus 87 raised to the composed with power close paren equals sine 87 raised to the composed with power. Подставим полученное значение в исходное выражение:
    36sin93sin87=36sin87sin87the fraction with numerator 36 sine 93 raised to the composed with power and denominator sine 87 raised to the composed with power end-fraction equals the fraction with numerator 36 sine 87 raised to the composed with power and denominator sine 87 raised to the composed with power end-fraction . Сократим дробь:
    Так как sin870sine 87 raised to the composed with power is not equal to 0, мы можем сократить числитель и знаменатель на это значение:
    361=3636 center dot 1 equals 36.

Ответ: 36. Хотите разобрать решение аналогичного примера с косинусами или тангенсами?

Форма ответа

Ваш аватар