Question 794900
find all the values of x in the interval [0,2pi] for
14 cos(x) + 7 sin(2x)=0
7(2cos(x)+sin(2x)=0
(2cos(x)+2sin(x)cos(x)=0
cos(x)+sin(x)cos(x)=0
cos(x)(1+sin(x))=0
cos(x)=0
x=π/2, 3π/2
1+sin(x)=0
sin(x)=-1
x=π
...
x=π/2, π, 3π/2