Question

E =4cos² 30° + 4 Ctg² 30° -5tan² 30° + 4cos² 60°​

Answer 1

$= 4 { \cos(30) }^{2} + 4 { \cot(30) }^{2} - 5 { \tan(30) }^{2} + 4 { \cos(60) }^{2} \\ \\ = 4{( \frac{ \sqrt{3} }{2} )}^{2} + 4 { ( \sqrt{3} ) }^{2} - 5 {( \frac{1}{ \sqrt{3} }) }^{2} + 4 {( \frac{1}{2} )}^{2} \\ \\ = 4( \frac{3}{4} ) + 4(3) - 5( \frac{1}{3} ) + 4( \frac{1}{4} ) \\ \\ = 3 + 12 - \frac{5}{3} + 1 \\ \\ = 16 - \frac{5}{3} \\ \\ = \frac{43}{3}$