Question 144399
Given : {{{P(x)= x^2 - 3x}}}
 {{{P(a)= a^2 - 3a}}}

 {{{P(a+h)= (a+h)^2 - 3(a+h)}}}

 {{{P(a+h)= (a^2+2ah +h^2 - 3a-3h)}}}


 {{{P(a+h) - P(a) = (a^2+2ah +h^2 - 3a-3h) -(a^2 - 3a) }}}
{{{P(a+h) - P(a) = +2ah +h^2 -3h   }}}
{{{P(a+h) - P(a) = h^2 -3h + 2ah  }}}