point ngede kak bantu ya ....

Bab Differensial dan Limit
Matematika SMA Kelas XI

2] f(x) = 4 sin x cos x
f(x) = 2 . (2 . sin x cos x)
f(x) = 2 . sin 2x
f'(x) = 2 . cos 2x . 2
f''(x) = 4 . (-sin 2x) . 2
f"(x) = -8 sin 2x

jawabannya E

3] lim ((1 - cos 2x)/x²)
   x→0
= lim ((1 - (1 - 2 sin² x))/x²)
  x→0
= lim ((2 sin² x)/x²)
   x→0
= 2

jawabannya E

4] lim ((9 - x)/(x² - 9) - (1/(x - 3)))
   x→3

= lim ((9 - x - x - 3)/(x² - 9))
  x→3

= lim ((6 - 2x) / ((x + 3) (x - 3)))
  x→3

= lim (2 (3 - x) / (- (3 - x) (x + 3))
  x→3

= 2/(-(3 + 3))
= 2/-6
= -1/3

jawabannya D