Let \( f(x) = 2\cos^{-1}x + 4\cot^{-1}x - 3x^{2} - 2x + 10, \, x \in [-1,1] \). If \([a,b]\) is the range of the function \( f \), then \( 4a - b \) is equal to:
\( 11 \)
\( 11 - \pi \)
\( 11 + \pi \)
\( 15 - \pi \)