Phương trình sin²3x – cos²4x = sin²5x – cos²6x có các nghiệm là:

A. x = $-\frac{\mathrm{\pi }}{18}$ + kπ, $k\in \mathbb{Z}$

B. x = $-\frac{\mathrm{\pi }}{18}$ + k$\frac{2\mathrm{\pi }}{3}$, $k\in \mathbb{Z}$

C. x = $-\frac{\mathrm{\pi }}{6}$ + kπ; $-\frac{\mathrm{\pi }}{18}$ + kπ, $k\in \mathbb{Z}$

D: Đáp án khác

A. $x=\frac{\pi }{3}+k2\pi ,k\in \mathbb{Z}$

B. $x=-\frac{\pi }{3}+k\frac{\pi }{2},k\in \mathbb{Z}$

C. $x=\pm \frac{\pi }{3}+k2\pi ,k\in \mathbb{Z}$

D. Đáp án khác

A. $\left[\begin{array}{l}x=-\frac{\pi }{4}+k2\pi \\ x=\frac{\pi }{8}+k\pi \\ x=k\frac{\pi }{2}\end{array}\right.,k\in \mathbb{Z}$

B. $\left[\begin{array}{l}x=\frac{\pi }{4}+k2\pi \\ x=\frac{\pi }{2}+k\pi \\ x=k\pi \end{array}\right.,k\in \mathbb{Z}$

C. $\left[\begin{array}{l}x=\frac{3\pi }{4}+k2\pi \\ x=-\frac{\pi }{2}+k\pi \\ x=k2\pi \end{array}\right.,k\in \mathbb{Z}$

D. $\left[\begin{array}{l}x=\frac{5\pi }{4}+k2\pi \\ x=\frac{3\pi }{8}+k\pi \\ x=k\frac{\pi }{4}\end{array}\right.,k\in \mathbb{Z}$

A. cot x = $\sqrt{3}$

B. cot 3x = $\sqrt{3}$

C. tan x = $\sqrt{3}$

D. tan 3x = $\sqrt{3}$

A. x = $-\frac{\mathrm{\pi }}{6}$ + k2π, $k\in \mathbb{Z}$

B. x = $-\frac{5\mathrm{\pi }}{3}$ + k$\frac{\mathrm{\pi }}{2}$, $k\in \mathbb{Z}$

C. x = $-\frac{\mathrm{\pi }}{6}$ + k2π; x = $\frac{7\mathrm{\pi }}{6}$ + k2π, $k\in \mathbb{Z}$

D: Đáp án khác

A. x = $-\frac{\mathrm{\pi }}{8}$ + kπ

B. x = $-\frac{\mathrm{\pi }}{4}$ + kπ

C. x = $-\frac{\mathrm{\pi }}{4}$ + kπ, $-\frac{\mathrm{\pi }}{8}$ + kπ; $\frac{5\mathrm{\pi }}{8}$ + kπ

D: Đáp án khác