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Evaluate: limx→01-cos2xx2 - Mathematics

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प्रश्न

Evaluate: `lim_(x -> 0) (1 - cos 2x)/x^2`

योग

उत्तर

Given that `lim_(x -> 0) (1 - cos 2x)/x^2`

= `lim_(x -> 0) (2 sin^2x)/x^2`  .......[cos 2x = 1 – 2 sin2x]

= `lim_(x -> 0) 2(sin x/x)^2`

= `2 xx 1`

= 2   .....`[because  lim_(x -> 0) sinx/x = 1]`

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अध्याय 13: Limits and Derivatives - Exercise [पृष्ठ २४०]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 13 Limits and Derivatives
Exercise | Q 17 | पृष्ठ २४०

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