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What is g[f(x)] of f(x)= and g(x)= `x^2 + 2` ? I am at the step of multiplying the...

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mashymash | Student, Undergraduate | Honors

Posted March 27, 2013 at 8:28 PM via web

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What is g[f(x)] of f(x)= and g(x)= `x^2 + 2` ? I am at the step of multiplying the square roots and am not sure how to finish it from there. 

g( )

= (  ) () + 2 

` `

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oldnick | Valedictorian

Posted May 8, 2013 at 5:40 AM (Answer #2)

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`f(x)= (x^2+2)^2+2=x^4+4x^2+4+2=x^4+4x^2+6`

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rakesh05 | High School Teacher | (Level 1) Assistant Educator

Posted May 14, 2013 at 7:11 AM (Answer #3)

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Given g(x)=x^2+2. But the expresion for f(x) is not given.

Now     g[f(x)]={(f(x))^2}+2.

Now suppose that f(x)=(x+1).

Then    g[f(x)]={(x+1)^2}+2

                      ={x^2+2x+1}+2

                       =x^2+2x+3.

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