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\(\displaystyle \lim_{x \to 0}\frac{1-\cos x + x.\sin x}{2x^2}=\)
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[ 5-6215 - op net sinds 13.2.2022-(E)-19.10.2026 ]
Translation in E N G L I S H
Oplossing - Solution
1ste manier : zonder de regel van de l'Hospital
\(\displaystyle \lim_{x \to 0}\frac{1-\cos x + x.\sin x}{2x^2}=\displaystyle \lim_{x \to 0}\frac{2.\sin^2 \frac x2+ x.\sin x}{2x^2}=\\\displaystyle \lim_{x \to 0}\frac{\sin^2 \frac x2} {x^2}+\displaystyle \lim_{x \to 0}\frac{\sin x} {2x}=\frac 14 + \frac 12 = \frac 34\)
2de manier : met de regel van de l'Hospital
\(\displaystyle \lim_{x \to 0}\frac{1-\cos x + x.\sin x}{2x^2}\left ( =\frac 00 \right )\overset{H}{=}\displaystyle \lim_{x \to 0}\frac{\sin x+ \sin x + x.\cos x }{4x}\\=\displaystyle \lim_{x \to 0}\frac{2\sin x}{4x}+\displaystyle \lim_{x \to 0} \frac{\cos x}{4}=\frac 24 + \frac 14 = \frac 34\)