Limit trigonometri bantu please

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llimit x→π/4  (cos 2x) / (x - π/4)
d'hopital
limit x→π/4  (- 2 sin 2x)/ (1) = -2 sin π/2= -2(0)= 0

limit x→0 ( 2 - 2 cos2x)/(x²)
limit x→0  2(1- cos 2x) / (x²)
limit x→0 2 (2 sin² 2x) / (x²)
limit x→0  2 (2)(2x)²/(x²) = 2(2)(4) =16