Step 1: Recall the property of skew-symmetric matrices
For a skew-symmetric matrix \( A \), \( A^T = -A \).
Step 2: Analyze \( AB + BA \)
Taking the transpose: \[ (AB + BA)^T = B^T A^T + A^T B^T = (-B)(-A) + (-A)(-B) = AB + BA. \] Thus, \( AB + BA \) is symmetric, as its transpose equals itself.
Let \[ f(x)=\int \frac{7x^{10}+9x^8}{(1+x^2+2x^9)^2}\,dx \] and $f(1)=\frac14$. Given that 

