Find the number of terms when the expression (1 + x)^10*(1 - x)^10 is expanded completely.
\((1 + x)^{10}*(1 - x)^{10}\\ =[(1 + x)(1 - x)]^{10}\\ =[1-x^2]^{10} \)
This will have 11 terms
\(1-10x^2+ ..... -10x^{18}+x^{20}\)