Question 935617
{{{y(x)=x-2}}}
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{{{y(x+h)=x+h-2}}}
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{{{y(x+h)-y(x)=x+h-2-(x-2)=h}}}
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{{{(y(x+h)-y(x))/h=h/h=1}}}
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{{{dy/dx=1}}}