sin10°怎么等于cos20°
cos20°cos10°+sin10°sin10°
sin40°*(1-sin10°)/[sin10°*(cos20°)^2]
cos20/(cos10+sin10)+sin10
化简((cos20°/sin20°)cos10°)+根号3(sin10°tan70°)-2cos40°
Sin10°cos60°sin50°cos20°sin90°不查表求值
(sin10°+sin20°)/(cos10°+cos20°)化简求值
sin70°cos20°-sin10°sin50°的值是多少?,麻烦给出过程
计算:sin10°cos20°sin30°cos40°=______.
化简[2sin50°+sin10°(1+3tan10°)]1+cos20°
(sin20*sin10)/(cos20*cos10)
化简{2sin50°+sin10°【1+(根号3tan10°)】根号(1加cos20)°
求cos20°cos10