How do you simplify using the sum and difference formula cos75cos75?

1 Answer
Binayaka C.
Dec 11, 2016

cos75=(sqrt3 -1)/(2sqrt2)cos75=√3−12√2

Explanation:

cos75 = cos (30+45) = cos30*cos45 - sin30*sin45 =(sqrt3/2)(1/sqrt2) - 1/2*(1/sqrt2) = (sqrt3 -1)/(2sqrt2)cos75=cos(30+45)=cos30⋅cos45−sin30⋅sin45=(√32)(1√2)−12⋅(1√2)=√3−12√2[Ans]

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