Question

2cosx-sqrt30=0

Answer 1

\[2cosx=\sqrt{30}\]
\[cosx=\frac{ \sqrt{30} }{ 2 }\]
\[x=\cos^{-1} \frac{ \sqrt{30} }{ 2 }\]
which is impossible unless the sqrt30 is a typo and its supposed to be
\[\sqrt{3}\]