Question 95250
f(x)=x^2-2, then f(x+2)-f(x)
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f(x+2) = (x+2)^2-2 
= x^2+4x+2
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f(x)=x^2-2
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Subtract f(x) from f(x+2) to get:
f(x+2)-f(x) = 4x+4
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Cheers,
Stan H.