Wiskunde Multiple Choice Vraag uit Gricha's Wiskundige Vragenbank

$\frac{\cot \, (180^{\circ}+\alpha )\cdot \sin \, (90^{\circ}-\alpha )} {\tan \, (-\alpha )\cdot \cos\, (180^{\circ}-\alpha) }=$	A. 1
	B. cot ² x
	C. − cot x
	D. tan ² x
	E. − 1

[ 4-5244 - op net sinds 23.6.09-(E)-24.10.2023 ]

Translation in E N G L I S H

$\frac{\cot \, (180^{\circ}+\alpha )\cdot \sin \, (90^{\circ}-\alpha )} {\tan \, (-\alpha )\cdot \cos\, (180^{\circ}-\alpha) }=$	A. 1
	B. cot ² x
	C. − cot x
	D. tan ² x
	E. − 1

Oplossing - Solution

$\frac{\cot \, (180^{\circ}+\alpha )\cdot \sin \, (90^{\circ}-\alpha )} {\tan \, (-\alpha )\cdot \cos\, (180^{\circ}-\alpha) }\\ =\frac{\cot \alpha \cdot \cos \alpha }{-\tan \alpha\cdot (-\cos \alpha ) }\\ =\;\cot^2 \alpha$