is gelijk aan
|
A. 1 |
| B. 2 |
| C. een negatief getal |
| D. 4 |
E.  |
[ 5-6689 - op net sinds 29.1.13-(E)-17.10.2026 ]
Translation in E N G L I S H
is equal to
|
A. 1 |
| B. 2 |
| C. a negative number |
| D. 4 |
E.  |
Oplossing - Solution
1ste manier : zonder de regel van de l'Hospital
\(\displaystyle\:\lim_{x\to 2}\:\frac{2^{x+2}-16}{4^x-16}=\lim_{x\to 2}\:\frac{4.2^x-4.4}{(2^2)^x-16}=\displaystyle\:\lim_{x\to 2}\:\frac{4.(2^x-4)}{(2^2)^x-16}\\=\displaystyle\lim_{x\to 2}\:\frac{4.(2^x-4)}{(2^x-4)(2^x+4)}=\displaystyle\:\lim_{x\to 2}\:\frac{4}{2^x+4}=\displaystyle\:\lim_{x\to 2}\:\frac{4}{4+4}=\cdots\)
2de manier : met de regel van de l'Hospital
\(\displaystyle\:\lim_{x\to 2}\:\frac{2^{x+2}-16}{4^x-16}\left(=\frac00\right)\overset{H}{=}\displaystyle\:\lim_{x\to 2}\:\frac{2^{x+2}.\ln2}{4^x.\ln 4}=\frac{2^4.\ln2}{4^2.\ln4}=\frac{\ln2}{\ln4}=\frac{\ln2}{2.\ln2}=\cdots\)