Limit tan(sqrt(x)) answer check please

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limit tan(sqrt(x)) answer check please!:)

Homework Statement


tan(sqrt(x))
locate discontinuities

The Attempt at a Solution


tan(sqrt(x))=
sin(sqrt(x))/cos(sqrt(x))

so x cannot= (pi/2)2 + (pi)n when n is an integer

I am just wondering if this is correct
 
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synergix said:

Homework Statement


tan(sqrt(x))
locate discontinuities

The Attempt at a Solution


tan(sqrt(x))=
sin(sqrt(x))/cos(sqrt(x))

so x cannot= (pi/2)2 + (pi)n when n is an integer

I am just wondering if this is correct
No.
There are a couple of things to consider:
  1. the domain of sqrt(x)
  2. the domain of the tangent function.
Changing tan(x) to sin(x)/cos(x) isn't any help, I don't believe.

If we let y = sqrt(x), y will be in the domain of the tangent function provided that y = \pi/2 + k\pi
IOW, \sqrt{x} = \pi/2 + k\pi, where k is an integer.
I believe you were on this track, but solved this equation incorrectly. Try again.
 


what does IOW mean? x must be greater then one and cannot equal ((pi/2 + (pi)n)^2 when n is a positive integer right?
 


IOW means either 'In Other Words' or 'Isle of Wight'. Pick one. I just looked it up. Mark44 is saying tan(sqrt(x)) isn't defined if sqrt(x)=pi/2+k*pi where k is an integer. Solve for x. It's not quite what you said it was.
 


If I were to say tan(sqrt(x)) is not defined if x is less then zero or equal to (Pi/2+K*pi)^2 where k is an integer would that be correct?
 


synergix said:
If I were to say tan(sqrt(x)) is not defined if x is less then zero or equal to (Pi/2+K*pi)^2 where k is an integer would that be correct?

Yes.
 
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