` cos 60^(@) cos 30^(@) + sin 60^(@) sin 30^(@)` का मान ज्ञात कीजिए |

Explanation

हम जानते है कि,
` cos60^(@)= (1)/(2), cos 30^(@) = (sqrt(3))/(2) , sin 60^(@) = (sqrt(3))/(2) , sin 30^(@) = (1)/(2)`
`therefore cos^(@) cos 30^(@) + sin 60^(@) sin 30^(@)`
` (1)/(2)xx(sqrt(3))/(2) + (sqrt(3))/(2) xx (1)/(2) = (sqrt(3 )+ sqrt(3))/(4) = (2sqrt(3))/(4) = sqrt(3)/(2)`