Find the number of terms when the expression (1 + x)^10*(1 - x)^10 is expanded completely.
Sorry if this is not correct, but I think that there would be 11 terms. Anyone willing to check?
Yes, you're right. It is because (1 + x)^10 (1 - x)^10 is just (1 - x^2)^10.
+186 
