tunjukkan tan 75 =2+ akar 3

jawab
tan 75 = 2 + √3
tan 75 = tan (45+30) = tan 45 + tan 30 / ( 1- tan 45 . tan 30)
tan 75 = ( 1 +  1/ √3) / ( 1 -1 (1/ √3))  | kalikan √3/√3
tan 75 = ( √3 + 1) /(√3 - 1) | kalikan (√3 + 1)(√3 + 1)
tan 75 = (√3 + 1)² /(3 -1) = (3 + 1 + 2√3)/(2)
tan 75 = (4 + 2√3)/(2)= (2 + √3)