Verified answer

This link has a step by step solution to your problem:

http://www.symbolab.com/solver/definite-integral-c...

Hope this helps

Use the integral by parts

or

formula

∫√(a^2 + x^2)dx = (x/2)√(a^2 + x^2) + (a^2/2)sinh^-1 (x/a)

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