Evaluate : `cos60^(@)cos30^(@)+ sin 60^(@)sin30^(@)` – InterviewSolution

InterviewSolution

1.	Evaluate : `cos60^(@)cos30^(@)+ sin 60^(@)sin30^(@)`
Answer» We know that , `cos60^(@)=(1)/(2),cos30^(@)=(sqrt(3))/(2),sin 60^(@) = (sqrt(3))/(2),sin=(1)/(2)` `:. cos60^(@) 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)`

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