Limit of sin(x)/x and tan(x)/x

Before you see this post,

see

A Property of Limit of A Function : f(x)/g(x),

Trigonometric Function : Sine, Cosine and Tangent,

Graph of Trigonometric Function : Sine, Cosine and Tangent

and

Radian

First, Let's divide the formula by sinθ.

There is a result.

Second, Let's divide the formula by tanθ. 

There is a result.