Question 323644
{{{f(x)=6x^2+5x}}}
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{{{f(x+h)=6(x+h)^2+5(x+h)}}}
{{{f(x+h)=6(x^2+2hx+h^2)+5x+5h}}}
{{{f(x+h)=6x^2+12hx+6h^2+5x+5h}}}
{{{f(x+h)=6x^2+(12h+5)x+h^2+5h}}}
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{{{f(x+h)-f(x)=6(x+h)^2+5(x+h)=6x^2+(12h+5)x+h^2+5h-6x^2-5x}}}
{{{f(x+h)-f(x)=6(x+h)^2+5(x+h)=12hx+h^2+5h}}}
{{{(f(x+h)-f(x))/h=12x+h+5}}}