Question

Find the third term in the expansion of (a+b)^9 in the simplest form

Answer 1

Answer:

$The\ third\ term\ is\ \boxed{36a^7b^2}$

Step-by-step explanation:

$\left(\begin{array}{c}9\\ 1\end{array}\right)=\dfrac{9}{1} =9\\\\\left(\begin{array}{c}9\\ 2\end{array}\right)=\dfrac{9*8}{2*1} =36\\\\\\(a+b)^9=a^9+\left(\begin{array}{c}9\\ 1\end{array}\right)a^8b+\left(\begin{array}{c}9\\ 2\end{array}\right)a^7b^2+....+b^9\\\\\\The\ third\ term\ is\ \boxed{36a^7b^2}$