## Trigonometry 7th Edition

4 + 2$\sqrt 3$ or 2 (2 + $\sqrt 3$)
Given expression = $( \tan 45^{\circ} + \tan 60^{\circ})^{2}$ = $( 1+ \sqrt 3)^{2}$ ( substituting for exact values of trigonometric functions) = ( 1 + $2\sqrt 3$ + 3) [ on expanding using identity $(a+b)^{2} = a^{2} + 2ab + b^{2}$] = 4 + 2$\sqrt 3$ or 2 (2 + $\sqrt 3$)