## How do you show a function is not uniformly continuous?

Proof. If f is not uniformly continuous, then there exists ϵ0 > 0 such that for every δ > 0 there are points x, y ∈ A with |x − y| < δ and |f(x) − f(y)| ≥ ϵ0. Choosing xn,yn ∈ A to be any such points for δ = 1/n, we get the required sequences.

## Is sin sin x uniformly continuous?

|sin(x)−sin(y)| is the distance between the y-coordiates of a and b. Hence, in this case |sin(x)−sin(y)|≤|x−y|. This gives us uniform continuity on (−π,π], so by periodciity the sine function is uniformly continuous on the entire line.

How do you prove X is uniformly continuous?

Let a,b∈R and aif and only if f can be extended to a continuous function ˜f:[a,b]→R (that is, there is a continuous function ˜f:[a,b]→R such that f=˜f∣(a,b)).

### Is sin2x uniformly continuous?

<|(x−y)(x+y)|<|(x+y)|δ, which is dependent on x so sin2x is not uniformly continuous.

### Does sin x converge uniformly?

Hence sin(x + 1/n) converges uniformly to sinx on R. 1 n x (x2 + 1/n2) = 0 · 1 x = 0. Also, limn→∞ fn(0) = limn→∞ 0 = 0.

Is Sinx continuous and differentiable?

Theorem The function sin x is differentiable everywhere, and its derivative is cos x.

## Which functions are uniformly continuous?

Every Lipschitz continuous map between two metric spaces is uniformly continuous. In particular, every function which is differentiable and has bounded derivative is uniformly continuous. More generally, every Hölder continuous function is uniformly continuous.

## Is sin x differentiable everywhere?

Is sin x 3 uniformly continuous?

f(x)=sinx3 for x∈R is not uniformly continuous. What would my first observation in checking uniform continuity is to check if its derivative is bounded. In this case its derivative f′(x)=3x2sinx3 which is unbounded.

### Why is Sinx not differentiable?

Sinx is a function in which at any point no discontinuity occurs and u can draw tangents. So its differentiable. @Mostafijur_Rahaman yup vertical tangent at a point means slope will be undefined as tan90 deg = not defined.. so the function having vertical tangent will be non-differentiable at that point..

### What means uniformly continuous?

In mathematics, a real function of real numbers is said to be uniformly continuous if there is a positive real number such that function values over any function domain interval of the size are as close to each other as we want.