Wiskunde Multiple Choice Vraag uit Gricha's Wiskundige Vragenbank

$https://latex.codecogs.com/png.image?\large \dpi{110}\log_2 \; \cos\left ( -\frac{\pi}{4} \right )$	A. = − 2
	B. = 2
	C. =
	D. =
	E. bestaat niet

[ 6-2624 - op net sinds 7.11.12-(E)-3.11.2023 ]

Translation in E N G L I S H

$https://latex.codecogs.com/png.image?\large \dpi{110}\log_2 \; \cos\left ( -\frac{\pi}{4} \right )$	A. = − 2
	B. = 2
	C. =
	D. =
	E. does not exist

Oplossing - Solution

$https://latex.codecogs.com/png.image?\dpi{110}\\ \log_2 cos\left ( -\frac{\pi}{4} \right )=\log_2 \cos\frac{\pi}{4}= \log_2\frac{\sqrt 2}{2}=\log_2 \frac{1}{\sqrt 2}\\=\log_2 1 - \log_2 \sqrt 2=0-\frac 12 \log_2 2=-\frac 12$