Question #e22ad

1 Answer
Feb 13, 2017

x=2npi+3pi/2
where n in NN

Explanation:

Consider the given equation
2tan(x/2)+2=0

Let's re-arrange that equation by subtracting 2 from either side, giving us
2tan(x/2)=-2

Now, we see that the value 2 is multiplied on both sides, so we'll divide by 2 on both sides, giving us
{cancel2tan(x/2)}/cancel2=-cancel2/cancel2

We end up with tan(x/2)=-1

Now, the value for which the tan functions give -1 in the range (0,2pi) would be either 3pi/4 or 7pi/4

If you notice either answer, you'll see the second answer is pi more than the first one, that is 7pi/4=pi+3pi/4

So, in a general case, the answers are npi+3pi/4

So, x/2=npi+3pi/4

If one were to find x, then by multiplying by 2, they'll get the answer they were looking for.