ĐK: \(x\ne-\dfrac{1}{2}+\dfrac{k\pi}{2}\)
\(cot\left(2x+1\right)=tan\dfrac{1}{2}\)
\(\Leftrightarrow cot\left(2x+1\right)=cot\left(\dfrac{\pi}{2}-\dfrac{1}{2}\right)\)
\(\Leftrightarrow2x+1=\dfrac{\pi}{2}-\dfrac{1}{2}+k\pi\)
\(\Leftrightarrow x=\dfrac{\pi}{4}-\dfrac{3}{4}+\dfrac{k\pi}{2}\)
1) Cot(4x+pi/4)+3=0
2) tan(1+2x)=2/3
Giải phương trình :
tanx/(1-tan^2x)=cot(x+pi/4)/2
Tan^2(2x-pi/4)=3
Tan^2x+cot^2x=2
tan^2x+cot^2x+2/sin2x=4
Giải các pt sau:
a) \(\sin\left(3x+60^o\right)=\dfrac{1}{2}\)
b) \(\cos\left(2x-\dfrac{\pi}{3}\right)=\dfrac{-\sqrt{2}}{2}\)
c) \(\tan\left(x+\dfrac{\pi}{6}\right)=\sqrt{3}\)
d) \(\cot\left(2x+\pi\right)=-1\)
Giải các Phương trình sau
a) \(sin^4\frac{x}{2}+cos^4\frac{x}{2}=\frac{1}{2}\)
b) \(sin^6x+cos^6x=\frac{7}{16}\)
c) \(sin^6x+cos^6x=cos^22x+\frac{1}{4}\)
d) \(tanx=1-cos2x\)
e) \(tan(2x+\frac\pi3).tan(\frac\pi3-x)=1\)
f) \(tan(x-15^o).cot(x+15^o)=\frac{1}{3}\)
cho α ϵ(π/2,3π/4),tanα/cotα=√5 -1/√5 +1.tính p=sin2αtanα+cos2αcotα+sin2α.
Giải PT
a) sin2 x + 2sinx - 3 = 0
b) 2cos x + cos 2x = 0
c) tanx + cotx + 2 = 0
d) sinx + cos2x + 1 = 0
e) tan x + cot 2x = 0
|2 tan x − 1| + |2 cot x − 1| = 2
