Question

How do you solve `cos(x+45)+cos(x-45)=sqrt2`?

Answer 1

Solution: `x=0^0`

Explanation:

`cos(x+45) + cos (x-45) =sqrt2 or cos x cos 45 cancel(- sinx sin45) + cosx cos45 cancel(+sinx sin45)=sqrt2 or 2 cosx cos45 =sqrt 2 or 2cosx *1/sqrt2 =sqrt 2 or 2 cos x =2 or cos x =1 ; cos 0 =1 :.x=0^0`
Solution: `x=0^0` [Ans]