How do you solve $(cos x - 1) (cos x - 4) = 0$ $(cos x - 1)(cos x - 4) = 0$ over the interval 0 to 2pi?

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Answer 1 · 2016-02-05T00:28:08

Hence $| cos x | \leq 1$ $abs(cosx)<=1$ we have that $cos x - 1 = 0 \Rightarrow cos x = 1$ $cosx-1=0=>cosx=1$

so we have that $x = 0$ $x=0$ or $x = 2 π$ $x=2pi$

How do you solve (cosx−1)(cosx−4)=0(cos x - 1)(cos x - 4) = 0 over the interval 0 to 2pi?