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Evaluate : limx→3x2-9x-3 if it exists by finding f(3-) and f(3+)

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प्रश्न

Evaluate : `lim_(x -> 3) (x^2 - 9)/(x - 3)` if it exists by finding `f(3^-)` and `f(3^+)`

योग
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उत्तर

`lim_(x -> 3) (x^2 - 9)/(x - 3) = lim_(x - 3^-) ((x + 3)(x - 3))/(x - 3)`

= `lim_(x -> 3^-) (x + 3)`

`lim_(x -> 3) (x^2 - 9)/(x - 3)` = 3 + 3

= 6   ........(1)

`lim_(x -> 3) (x^2 - 9)/(x - 3) = lim_(x -> 3^+) (x + 3)`

= 3 + 3

= 6   .......(2)

From equations (1) and (2) we get

`lim_(x -> 3) (x^2 - 9)/(x - 3) = lim_(x -> 3^+) (x^2 - 9)/(x - 3)` = 6

∴ `lim_(x -> 3) (x^2 - 9)/(x - 3)` = 6

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Differential Calculus - Limits and Continuity - Exercise 9.1 [पृष्ठ ९८]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 9 Differential Calculus - Limits and Continuity
Exercise 9.1 | Q 22 | पृष्ठ ९८

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