How to find area and value of p between region with integration?

Area is 5 according to my calcs, i dont know how to find the p value though.

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1 Answer

For a:
The area of A is #int_1^2(10/(x^2))dx = [-10/x]_1^2 = -10/2 +10/1 = -5 + 10 = 5#
For b:
p is in between 2 and 5 and you want to find where p is so
#int_2^p(10/x^2)dx = int_p^5(10/x^2)dx#
#=> [-10/x]_2^p=[-10/x]_p^5#
#=> -10/p + 10/2 = -10/5 + 10/p#
#=> -10/p+5 = -2 + 10/p#
#=> 7=20/p#
#=> p=20/7#