Step-by-step explanation:
sin(2x) = 2sin(x)cos(x)
2sin(x)cos(x) - cos(x) = 0
so one solution is cos(x) = 0.
=> x = pi/2 and 3pi/2 (90° and 270°)
for cos(x) <> 0 we have then
2sin(x) - 1 = 0
2sin(x) = 1
sin(x) = 1/2
=> x = pi/6 and 5pi/6 (30° and 150°)
9. 5y
10.10x^2-1
not done
Answer:
the answer is yes
Step-by-step explanation:
trust me