<PRE><B>Question 1091538</B>
f(x) = x^3 + 3x ^2 + 4x - 7 and g(x) = -7x^4 + 5x^3 +x^2 - 7.
 What is the coefficient of x^3 in the sum f(x) + g(x)?
&lt;pre&gt;Just line them up as below and add them vertically term by term:

{{{matrix(4,11,
       &quot;f(x)&quot;, &quot;&quot;=&quot;&quot;,    &quot;&quot;,    &quot;&quot;,   x^3, &quot;&quot;+&quot;&quot;, 3x^2, &quot;&quot;+&quot;&quot;, 4x, &quot;&quot;-&quot;&quot;, 7, 
       &quot;g(x)&quot;, &quot;&quot;=&quot;&quot;, -7x^4, &quot;&quot;+&quot;&quot;,  5x^3, &quot;&quot;+&quot;&quot;,  x^2,    &quot;&quot;, &quot;&quot;, &quot;&quot;-&quot;&quot;, 7,
&quot;----&quot;,&quot;----&quot;,&quot;----&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,&quot;---&quot;,
&quot;f(x)&quot;+&quot;g(x)&quot;, &quot;&quot;=&quot;&quot;, -7x^4, &quot;&quot;+&quot;&quot;,  6x^3, &quot;&quot;+&quot;&quot;, 4x^2, &quot;&quot;+&quot;&quot;, 4x, &quot;&quot;-&quot;&quot;,14)}}}

Now all you have to do is look at the bottom line and see what the 
coefficient of x&lt;sup&gt;3&lt;/sup&gt; is!

Edwin&lt;/pre&gt;</PRE>