LET Y = COS X
Then you have
4y^2-4y-1=0
Then use the quadratic equation to solve for y. then put for y, the original value...cosx= solution, and solve for x.
Hi, can someone please solve this step-by-step for me? I really don't get it...
Directions: Use the quadratic formula to solve the equation in the interval [0,2PI). Then use a graphing utility to approximate the angle x.
4cos^2x-4cosx-1=0
thanks.
1 answer