SOLUTION: 1.Solve the equation 2cos x-1=0, 0<x<2pi
2. Solve the equation (cos^2)x-(sin^2)x=cos x, 0<x<2pi
Algebra.Com
Question 864465: 1.Solve the equation 2cos x-1=0, 0
2. Solve the equation (cos^2)x-(sin^2)x=cos x, 0
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
1.Solve the equation
2cos x-1=0
cos(x) = 1/2
-----
x = pi/3 or x = -pi/3
==================================
2. Solve the equation (cos^2)x-(sin^2)x=cos x, 0
2cos^2(x)-1 = cos(x)
-----
2cos^2(x) - cos(x) -1 = 0
-------
cos(x) = [-1 +- sqrt(1-4*2*-1)]/4
-------
cos(x) = [-1 +- 3]/4
---
cos(x) = -3/4 or cos(x) = 1/2
------
x = arccos(-3/4) or cos(x) = 1/2
-------
x = 138.59 or x = 60 degrees
------------------------------------
Cheers,
Stan H.
--------------------------
RELATED QUESTIONS
Solve the equation for x, on the interval 0 is less than or equal to x and 2pi is greater (answered by Alan3354)
Solve the following for 0 < x < 2pi
(sin x + cos x)^2 =... (answered by lwsshak3,Alan3354)
Solve the following equation on the interval [0, 2pi]
cos^2 x + 2 cos x + 1 =... (answered by josgarithmetic)
solve the equation, [0, 2pi)
a)... (answered by lwsshak3)
Solve the equation on the interval 0 (answered by ewatrrr)
Please help me solve this equation: {{{ cos^2(x)+2sin(x)cos(x)-sin^2(x)=0 }}} with the... (answered by Edwin McCravy)
Solve the equations of [0, 2pi]:
cosx(2sinx-1)=0
and... (answered by lwsshak3)
Solve the equation for 0≤x≤{{{2pi}}}. Write your answer as a multiple of... (answered by Gogonati,Alan3354)
Solve the following equation: cos(x/3 - pi/4) = 1/2 , x is btw 0 and... (answered by Alan3354)