Answer:
81/5
Explanation:
See image.
I always think drawing these out helps.
I had to find lower limit for x by finding when 1/x^2=4
x^2=1/4
This implies x=1/2 since in the picture x is positive.
We need to evaluate
Integral( 4 - 1/x^2 , from x=1/2 to x=5)
Or
Integral( 4 - x^-2 , from x=1/2 to x=5)
=4x+x^-1 ] from x=1/2 to x=5
(4×5+5^-1)-(4×1/2+(1/2)^-1)
(20+1/5)-(2+2)
20-(2+2)+1/5
20-4+1/5
16+1/5
81/5