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Find the limit: `lim_(x->16) (16-x)/(sqrtx-4)` `` ` `

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cflorie | Student, Undergraduate | eNoter

Posted June 21, 2012 at 1:33 AM via web

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Find the limit:

`lim_(x->16) (16-x)/(sqrtx-4)`

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hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted June 21, 2012 at 1:55 AM (Answer #1)

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`lim_(x->16) (16-x)/(sqrtx - 4)`

First we plug in x= 16 ==> lim = 0/0

Then, we know that 16 is the root for both numerator and denominator.

Therefore, we will need to factor and reduce common factor between numerator and denominator.

`==> lim_(x->16) (16-x)/(sqrtx-4) = lim_(x->16) ((4-sqrtx)(4+sqrtx))/(sqrtx-4)`

`= lim_(x->16) (-(4+sqrtx)) = lim_(x->16) (-4-sqrtx)`

` = -4-sqrt16= -4-4= -8`

`==> lim_(x->16) (16-x)/(sqrtx-4)= -8`

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