SOLUTION: How would I solve (tanX-1)(cosX+1)=0? over the interval [0,2pi]

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Question 548857: How would I solve (tanX-1)(cosX+1)=0? over the interval [0,2pi]
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
How would I solve (tanX-1)(cosX+1)=0? over the interval [0,2pi]
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The expression will equal zero if either of the two factors is zero
So we need to solve:
tan(x) - 1 = 0 -> tan(x) = 1
cos(x) + 1 = 0 -> cos(x) = -1
x = arctan(1) = pi%2F4 and 5%2Api%2F4 on the interval [0,2pi]
x = arcos(-1) = pi
The solutions can be seen from the zero crossings on the graph below:
graph%28300%2C300%2C0%2C2%2Api%2C-1%2C1%2C%28tan%28x%29-1%29%2A%28cos%28x%29%2B1%29%29