ANSWER
15 square unit.
Step-by-step explanation
Step 1:
Recall that the right endpoint Riemann sum for
Step 2:
Note, if f(x) is continuous, then:
Step 3:
Now, applying the limit of the Reimann sums to evaluate the integral:
Please, carefully check my working:
Hence, using the concept of the definite integral, the total area between the graph of f(x) and the x-axis by taking the limit of the associated right Riemann sum is 15 square unit.