Вычислите sin 75 *sin15
Sin75⁰·sin15⁰=1/2·[cos(75⁰-15⁰)-cos(75⁰+15⁰)]=
=1/2·(cos60⁰-cos90⁰)=1/2·(√3/2-0)=√3/4;
Оцени ответ
Sin75⁰·sin15⁰=1/2·[cos(75⁰-15⁰)-cos(75⁰+15⁰)]=
=1/2·(cos60⁰-cos90⁰)=1/2·(√3/2-0)=√3/4;