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• you would substitute x in f(x) with (x+h): F(x+h)-F(x)= 2(x+h)+1 - (2x+1)= 2x+2h+1-2x-1= 2x and 1 cancel out leaving you 2h as your answer. If you have to take it a step further and substitute h for H(x) then you would continue as so... …

  in How do I do a problem like this F(x+h)? Comment by byob June 2021
• you would substitute x in f(x) with (x+h): F(x+h)-F(x)= 2(x+h)+1 - (2x+1)= 2x+2h+1-2x-1= 2x and 1 cancel out leaving you 2h as your answer. If you have to take it a step further and substitute h for H(x) then you would continue as so... …

  in How do I do a problem like this F(x+h)? Comment by byob May 2021