Question 1187157
<br>
In the expansion of {{{(1-ax)^24}}}, the coefficient of the x^2 term is<br>
{{{C(24,2)(1^22)((-a)^2)}}}<br>
Given that that coefficient is 69, we have<br>
{{{((24*23)/2)(1)(x^2)=69}}}
{{{12x^2=3}}}
{{{x^2=1/4}}}
{{{x = 1/2}}}  OR  {{{x = -1/2}}}<br>
So there are going to be two different possible answers for the coefficient of x^3.<br>
ANSWER #1: {{{C(24,3)(1^21)((1/2)^3)=253}}}<br>
ANSWER #2: {{{C(24,3)(1^21)((-(1/2))^3)=-253}}}<br>