nilai fungsi f(x)= 3 tan 2(x-phi/8)untuk nilai x = phi/4 adalah

NIlai Fungsi Trigonometri

f(x)= 3 tan (x - π/8)
f(π/4) = 3 tan (π/4 - π/8)
f(π/4) = 3 tan (π/8)
π = 180°
f(45) = 3 tan (22,5)
.
tan 45 = ( 2 tan 22,5)/( 1 - tan² 22,5)
1 = (2 tan 22,5 )/ (1 - tan² 22,5)
2 tan 22,5 = 1 - tan² 22,5
tan² 22,5 + 2 tan 22,5 = 1
(tan 22,5 + 1)² = 1 + 1
tan 22,5 + 1 = √2
tan 22,5 = -1 + √2
.
f(45) = 3  tan 22,5
f(π/4) = 3 (-1 + √2)
f(π/4) = -3 + 3√2