Phương trình 6sin^2 x +7 căn 3 sin2x -8cos^2 x =6 có các nghiệm là

A. $x=\frac{\mathrm{\pi }}{2}+k\mathrm{\pi } \mathrm{hoặc} \mathrm{x}=\frac{\mathrm{\pi }}{6}+\mathrm{k\pi }, \mathrm{k}\in \mathrm{\mathbb{Z}}$

B. $x=\frac{\mathrm{\pi }}{4}+k\mathrm{\pi } \mathrm{hoặc} \mathrm{x}=\frac{\mathrm{\pi }}{3}+\mathrm{k\pi }, \mathrm{k}\in \mathrm{\mathbb{Z}}$

C. $x=\frac{\mathrm{\pi }}{8}+k\mathrm{\pi } \mathrm{hoặc} \mathrm{x}=\frac{\mathrm{\pi }}{12}+\mathrm{k\pi }, \mathrm{k}\in \mathrm{\mathbb{Z}}$

D. $x=\frac{3\mathrm{\pi }}{4}+k\mathrm{\pi } \mathrm{hoặc} \mathrm{x}=\frac{2\mathrm{\pi }}{3}+\mathrm{k\pi }, \mathrm{k}\in \mathrm{\mathbb{Z}}$