How many terms are in the expansion of (2x - 1/y)^10?

Step 1 (Binomial Theorem): The Binomial Theorem states that for any positive integer $n$, the expansion of $(x+y{)}^n$ is given by:

Step 2 (Count the Terms): The summation index $k$ ranges from $0$ to $n$. The total number of terms in the expanded form is exactly:

Step 3 (Direct Application): In the expression ${\left(2x-\frac{1}{y}\right)}^{10}$, the power $n$ is $10$. Therefore, the number of terms in the expansion is:

Step 4 (Conclusion): The expansion contains exactly 11 terms.