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प्रश्न
Verify each of the following:
(ii)`cos 60^0 cos 30^0+ sin 60^0 sin30^0`
उत्तर
`cos 60^0 cos 30^0+ sin 60^0 sin30^0`
=`(1/2) xx(sqrt(3)/2) + (sqrt(3)/2) xx(1/2) = sqrt(3)/4 + sqrt(3)/4 =sqrt(3)/2`
Also, cos `30^0 = sqrt(3)/2`
∴`cos 60^0 cos 30^0+ sin 60^0 sin30^0= cos 30^0`
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