Question 1 Report
3cos2x - sinx = 0
cos 2A = 1 – 2 sin2A
3(1 - 2sin2x) - sinx = 0
3 - 6sin2x -sinx = 0
let sinx = p
3 - 6p2 -p = 0
-6p2 - p +3 = 0
factors of p in the eqn:
p = 0.7953 or 0.6287
when p = 0.7953
p = sinx
x = sin−1 p
x = sin−1(0.7953)
x = 52.68º
when p = 0.6287
p = sinx
x = sin−1 p
x = sin−1(0.6287)
x = 38.95º
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