Question 988892
{{{f(x)=2x^2+7x+9}}}



{{{f(x+h)=2(x+h)^2+7(x+h)+9}}}



{{{f(x+h)=2(x^2+2xh+h^2)+7(x+h)+9}}}



{{{f(x+h)=2x^2+4xh+2h^2+7x+7h+9}}}



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{{{D = (f(x+h)-f(x))/h}}}



{{{D = (2x^2+4xh+2h^2+7x+7h+9-(2x^2+7x+9))/h}}}



{{{D = (2x^2+4xh+2h^2+7x+7h+9-2x^2-7x-9)/h}}}



{{{D = (4xh+2h^2+7h)/h}}}



{{{D = (h*(4x+2h+7))/h}}}



{{{D = (highlight(h)*(4x+2h+7))/(highlight(h))}}}



{{{D = (cross(h)*(4x+2h+7))/(cross(h))}}}



{{{D = 4x+2h+7}}}



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The final simplified answer is {{{D = 4x+2h+7}}}