cos20°sin40°+sin20°sin50°=?

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cos20°sin40°+sin20°sin50°=?cos20°sin40°+sin20°sin50°=?cos20°sin40°+sin20°sin50°=?cos20°sin40°+sin20°

cos20°sin40°+sin20°sin50°=?
cos20°sin40°+sin20°sin50°=?

cos20°sin40°+sin20°sin50°=?
cos20°sin40°+sin20°sin50°
=cos20°cos50°+sin20°sin50°
= cos(50°-20°)
=cos30°
=√3/2

cos20°sin40°+sin20°sin50°
=cos20°sin40°+sin20°cos40°
=sin(20°+40°)
=sin60°
=√3/2