1.
If f(x)={4sinx+cosx,xπ2asinx+b,π2<x<π2cosx+2,xπ2f(x) = \begin{cases} -4\sin x + \cos x, & x \leq -\dfrac{\pi}{2} \\[8pt] a\sin x + b, & -\dfrac{\pi}{2} < x < \dfrac{\pi}{2} \\[8pt] \cos x + 2, & x \geq \dfrac{\pi}{2} \end{cases} is continuous, then: