02Jan

Найдите значение выражения (cos18*sin18)/cos126

Posted by cat30 | Posted at Jan 02, 2014 | Categories: Алгебра

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[latex] frac{cos18cdot sin18}{cos126}=frac{frac{1}{2}sin36}{cos(90+36)}=frac{sin36}{2cdot (-sin36)}= -frac{1}{2} [/latex]

Jan 03, 2014 00:57

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