Does anyone know how to solve these two problems in the range [0, 2pie]?
2cos(2x) = 1
cos (2x) + 5 cos(x) = 2
I don't know why but I always have trouble with these. If anyone could help, it'd be greatly appreciated! thanks
2007-04-29 15:41:06 · 2 answers · asked by Honey 1 in Science & Mathematics ➔ Mathematics
Don't get spooked by the trig terms. After all, if you had 2y = 1
Could you solve it? If so, this problem should be duck soup. First, cos (2x) = 0.5. Actually, your interval should be a DOMAIN, not a range. In that interval, 2x = pi/3 and 5pi/3.
For equation 2, there is a cos double-angle formula, which I have forgotten with time. So it solution is yours.
2007-04-29 15:57:26 · answer #1 · answered by cattbarf 7 · 0⤊ 0⤋
looks like mumbo-jumbo to me!!!!!!!!!!!!!!!!!!!!!
2007-04-29 15:46:49 · answer #2 · answered by Anonymous · 0⤊ 0⤋