add img in git readme.md file code example

Example 1: adding a preview image in readme.md

// method 1


// method 2
![Test Image 3](/3DTest.png)
![Test Image 4](https://github.com/tograh/testrepository/3DTest.png 112)

// last method

Example 2: github readme.md add image

![GitHub Logo](/images/logo.png)
Format: ![Alt Text](url)