Trapezoidal Rule for Approximate Value of Definite Integral

In the field of numerical analysis, Trapezoidal rule is used to find the approximation of a definite integral. The basic idea in Trapezoidal rule is to assume the region under the graph of the given function to be a trapezoid and calculate its area. 
It follows that:

For more accurate results the domain of the graph is divided into n segments of equal size as shown below: 

Grid spacing or segment size h = (b-a) / n. 
Therefore, approximate value of the integral can be given by: 

Output: 

Value of integral is 0.7842

References:
https://en.wikipedia.org/wiki/Trapezoidal_rule