Question 183014
I'll do the first two to get you started


# 1


{{{f(x)= 2x + 5 }}} Start with the given function.



{{{f(b^2)= 2b^2 + 5 }}} Plug in {{{x=b^2}}}. In other words, replace each "x" with {{{b^2}}}


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# 2


{{{g(x)= 3x^2-1 }}} Start with the given function.



{{{g(a+1)= 3(a+1)^2-1 }}} Plug in {{{x=a+1}}}. In other words, replace each "x" with {{{a+1}}}



{{{g(a+1)= 3(a^2+2a+1)-1 }}} FOIL



{{{g(a+1)= 3a^2+6a+3-1 }}} Distribute



{{{g(a+1)= 3a^2+6a+2 }}} Combine like terms.