If #f( x ) = \frac { 3} { x + 2} - \sqrt { x - 3}#, what is #f(19)#?

1 Answer
Mar 14, 2017

Where ever #x# is you write 19 instead

#4 1/7" or " -3 6/7#

Explanation:

Set #" "f(19)->y=3/(19+2)-sqrt(19-3)#

#3/21-sqrt(16)#

#[(3-:3)/(21-:3)]+-4#

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Note that #(-4)xx(-4)=(+4)xx(+4) = 16#
So #-sqrt(16)=+-4#
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#1/7+-4#

#4 1/7" or " -3 6/7#