- #1
- 49
- 0
Find the x-coordinate of all points on the curve y = sin(2x) + 2 sin(x) at which the tangent line is horizontal. Consider the domain x = [0,2π).
f'(x)=2cos2x+2cosx
f'(x)=2cos2x+2cosx
Thanks.Nice diagram mystic
If you're trying to find where [tex]cos(2x)+cos(x)=0[/tex], you can use the formula [tex]cos(2x)=2cos^2(x)-1[/tex] and then you have a quadratic in cos(x) which you can solve.