If n is a positive integer and f(n) is the coeffcient of xn in the expansion of (1 + x)(1-x)n, then f(2023) =
The variance of the following grouped data is:
For what value of \( \alpha \), the matrix A is a singular matrix if \(A=\begin{bmatrix} 1 & 3 & \alpha+2 \\[0.3em] 2 & 4 & 8 \\[0.3em] 3 & 5 & 10 \end{bmatrix}\) ?
The eccentricity of \((\frac {x}{25})^2 + (\frac {y}{16})^2 = 1\) is:
Note: Assuming the intended equation is \( \frac{x^2}{25} + \frac{y^2}{16} = 1 \) based on the options. The literal interpretation \( \frac{x^2}{625} + \frac{y^2}{256} = 1 \) yields\(e =\frac {\sqrt{369}}{25}\), which is not among the options.