c
Step-by-step explanation:
Using Pascal's triangle, the expansion, although EXTREMELY lengthy, will help you find the 7th term. Â I am going to type out the expansion only up til the 7th term (although there are actually 10 terms because we are raised to the power of 9). Â If you would like to learn how to use Pascal's Triangle for binomial expansion, you will need to visit a good website that explains it because it's just too difficult to do it via this website.
The expasion is as follows (up to the 7th term):
That last term is the 7th term. Â You find out its value by multiplying all the numbers together and adding on the c^3d^6. Â Again those come from Pascal's triangle, and it's one of the coolest math things ever. Â I encourage you to take the time to explore how it works.