document.write( "Question 201560: Evaluate the function.\r
\n" ); document.write( "\n" ); document.write( "Given that f(x) = (sqrt x^2+1)/(x-1) , find f(-3).
\n" ); document.write( " A) (sqrt 10)/(-4) ≈ -0.7906
\n" ); document.write( " B) (sqrt 10)/(-4) ≈ 0.7906
\n" ); document.write( " C) (sqrt 10)/(-4) ≈ -25.0000
\n" ); document.write( " D) (sqrt 10)/(-4) ≈ -1.25 \n" ); document.write( "

Algebra.Com's Answer #151768 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Just substitute -3 in place of

and do the arithmetic. But since you are given 4 answers, let's look at them. They are all

. Since

is positive (by convention -- the negative square root would be designated

), and the denominator is clearly negative, the quotient must be negative. Goodbye Answer B.\r
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\n" ); document.write( "\n" ); document.write( "If it were Answer C, then

would have to be equal to 100. Since we know that

is less than 10, that can't be true. Goodbye, Answer C.\r
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\n" ); document.write( "\n" ); document.write( "If it is Answer D, then

has to be larger than 4, but if it is Answer A, then

has to be smaller than 4. We know that 3 times 3 equals 9, so 3 is smaller than the square root of 10, but 4 times 4 is 16, so 4 is larger than the square root of 10.\r
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\n" ); document.write( "\n" ); document.write( "And I never touched a calculator...\r
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\n" ); document.write( "\n" ); document.write( "John
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