How does $f(x) = x - [x]$ behave at $x = 1$ ?

Not continuous: the left and right limits differCorrect answerYour answerContinuous at the pointCorrect answerYour answerNot continuous: the limit exists but differs from the valueCorrect answerYour answerNot continuous: the function has no value thereCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

Just left of 1, $[x] = 0$ , so $f(x) = x \to 1$ . At 1 and just right of it, $[x] = 1$ , so $f(x) = x - 1 \to 0$ .
The left limit 1 and right limit 0 differ.

Worth noting

The fractional part drops back to 0 at every integer.

Concept: Testing continuity at a point
Typical timeTypical: 90 s
Your timeYours: —

The rule this testsContinuity at a point

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How does f(x)=x−[x]f(x) = x - [x]f(x)=x−[x] behave at x=1x = 1x=1?

Explanation

How does $f(x) = x - [x]$ behave at $x = 1$ ?