SOLUTION: Solve the equation for x, on the interval 0 is less than or equal to x and 2pi is greater than x: sin(2x)+cos(3x)=0 Here is what I have so far: 2sin(x)cos(x)+ cos(x+2x)=0 2sin(

Algebra.Com
Question 797443: Solve the equation for x, on the interval 0 is less than or equal to x and 2pi is greater than x:
sin(2x)+cos(3x)=0
Here is what I have so far:
2sin(x)cos(x)+ cos(x+2x)=0
2sin(x)cos(x) +cos(x)cos(2x)- sin(x)sin(2x)=0
2sin(x)cos(x) +cos(x)[2cos^2(x-1)]- sin(x)[2sin(x)cos(x)]=0
2sin(x)cos(x) +2cos^3(x)- cos(x)- 2sin^2(x)cos(x)=0
cos(x)[2sin(x) +2cos^2(x)-1-2sin^2(x)]=0

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
Solve the equation for x, on the interval 0 is less than or equal to x and 2pi is greater than x:
sin(2x)+cos(3x)=0
Here is what I have so far:
2sin(x)cos(x)+ cos(x+2x)=0
2sin(x)cos(x) +cos(x)cos(2x)- sin(x)sin(2x)=0
2sin(x)cos(x) +cos(x)[2cos^2(x-1)]- sin(x)[2sin(x)cos(x)]=0
2sin(x)cos(x) +2cos^3(x)- cos(x)- 2sin^2(x)cos(x)=0
cos(x)[2sin(x) +2cos^2(x)-1-2sin^2(x)]=0
------------
cos(x) = 0
--> x = pi/2, 3pi/2
---------
2sin(x) +2cos^2(x)- 1 - 2sin^2(x) = 0
2sin(x) +2(1-sin^2(x))- 1 - 2sin^2(x) = 0
2sin(x) +2 - 2sin^2(x))- 1 - 2sin^2(x) = 0
2sin(x) + 1 - 4sin^2(x)) = 0
4sin^2 - 2sin - 1 = 0
sub for sin(x), solve the quadratic, etc.

RELATED QUESTIONS

Please solve the equation: (x is less than or equal to 2pi and greater than or equal to... (answered by lwsshak3)
Solve for x in the equation 3sin^2x = cos^2x; 0 (answered by stanbon)
Solve the equation for values for x greater than or equal to 0 and less than 2pi. Write... (answered by lwsshak3)
please solve the equation (x is greater than or equal to 0 and less than or equal to 2pi) (answered by Alan3354)
Solve equation, sin(2x) - sinx - 2cosx + 1 = 0, on the interval 0 < or equal x <... (answered by Boreal)
Solve the equation on the interval 0 less than or equal to theta which is less than 2pi. (answered by solver91311)
2 sin^2x+sinx=1 Find all solutions to each equation for 0 less than or equal too x... (answered by stanbon)
solve 2sinx-1= 0 for 0 is less than or equal to x less than 2pi (answered by god2012)
cos5xcos2x+sin5xsin2x= -1 for x is greater or equal to 0, and less than or equal to... (answered by Fombitz)