Thinking Mathematically (6th Edition)

Earlier solution of problems like ${{x}^{2}}+1=0$ and $\sqrt{-49}$ were thought to be impossible, then there is a Greek mathematician and engineer Heron of Alexandria is the one to discover the imaginary number to find the solution above mentioned problem. Application: Imaginary numbers are used to find the solution of the square root of the negative numbers. Curiosities: curiosities related to imaginary numbers are: The square root of imaginary number $i$has both real and imaginary parts.