20-22 please bantuannya bang
Matematika
JordanNiron
Pertanyaan
20-22 please bantuannya bang
1 Jawaban
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1. Jawaban whongaliem
no.20 dan 21 soal sama ...
21) misal 4x - 8 = 4 A
4(x - 2) = 4 A
x - 2 = 4A / 4
x - 2 = A karena x ⇒ 2 maka A ⇒ 0
[tex] \lim_{x \to \ 2} \frac{6x - 12}{tan (4x - 8)} = \lim_{x \to \ 2} \frac{6 (x - 2)}{tan 4(x - 2)} [/tex]
[tex]= \lim_{A \to \ 0} \frac{6 A}{tan 4A} [/tex]
[tex]= 6 . \lim_{A \to \ 0} \frac{A}{tan 4A} [/tex]
[tex]= 6 . \frac{1}{4} [/tex]
[tex]= \frac{3}{2} [/tex]
[tex]22) \lim_{x \to \ 0} \frac{sin x + sin 3x}{tan 2x . cos x} = \lim_{x \to \ 0} \frac{2 .sin 2x . cos (- x)}{tan 2x . cos x} [/tex]
[tex]= \lim_{x \to \ 0} \frac{2 .sin 2x . cos x}{tan 2x . cos x} [/tex]
[tex]= \lim_{x \to \ 0 } \frac{2.sin 2x}{tan 2x} X \frac{2x}{2x} [/tex]
[tex]= 2 . \lim_{x \to \ 0} \frac{2x}{tan x} \frac{sin 2x}{2x} [/tex]
= 2 . 1 . 1
= 2