we have the function
y=-x^2/2+x+5
Interval [-2,3]
step 1
Calculate the width of each rectangle
(3-(-2))/5=5/5=1
intervals of each rectangle
1) [-2,-1] ----> right endpoint -1
2) [-1,0] ----> right endpoint 0
3) [0,1] ----> right endpoint 1
4) [1,2] ----> right endpoint 2
5) [2,3] ----> right endpoint 3
step 2
Calculate the area of each rectangle
Find out the height of each rectangle ( value of y)
A=W*y
Remember that
w=1
so
1) For x=-1, y=-(-1)^2/2+(-1)+5 ----> y=