10. The equation of the tangent line to the curve $y = 2 \sin x + \cos x$ at the point $( \pi , - 1 )$ is A. $x - y - \pi - 1 = 0$ B. $2 x - y - 2 \pi - 1 = 0$ C. $2 x + y - 2 \pi + 1 = 0$ D. $x + y - \pi + 1 = 0$
Given that the ellipse $C$ has foci $F _ { 1 } ( - 1,0 ) , F _ { 2 } ( 1,0 )$, and passes through
10. The equation of the tangent line to the curve $y = 2 \sin x + \cos x$ at the point $( \pi , - 1 )$ is\\
A. $x - y - \pi - 1 = 0$\\
B. $2 x - y - 2 \pi - 1 = 0$\\
C. $2 x + y - 2 \pi + 1 = 0$\\
D. $x + y - \pi + 1 = 0$