The set of points of continuity of the function f(x) =12−cos2x is:
{x:π4+2nπ≤x≤3π4+2nπ,n∈I}
{x:5π4+2nπ≤x≤7π4+2nπ,n∈I}
{x:π4+2nπ≤x≤3π4+2nπ}∪{x:5π4+2nπ≤x≤7π4+2nπ}
None of these
The function f(x) is continuous at all points where 12−cos2x≥0 ⇒ |cosx|≤12
⇒ π4+2nπ≤x≤3π4+2nπ
Or ⇒ 5π4+2nπ≤x≤7π4+2nπ,n∈I