You can put this solution on YOUR website! f(x)=1-1/(x+2)^2
f(x+h)=1-1/(x+h+2)^2
=1-1/(x^2+2xh+4x+4h+h^2+4)
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=[(x+2)^2-1]/(x+2)^2
=(x^2+4x+3)/(x+2)^2
((x+h)^2+4(x+h)+3))/(x+h+2)^2
(x^2+2xh+h^2+4x+4h+3)/(x+h+2)^2
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f(2x+3)=1-1/(2x+3+2)^2
=1-1/(2x+5)^2
=[(2x+5)^2)-1]/(2x+5)^2
=(4x^2+20x+24)/(2x+5)^2
=4(x^2+5x+6)/(2x+5)^2. The numerator factors, but nothing can be simplified as a result
