# Integral with exponential and square root

I need help with the following indefinite integral:

$\int \sqrt{x^2-a^2} \,e^{b x} dx$

where $a$ and $b$ are positive constants. Thanks!

• from where Comes that integral? i don't think that we can get a solution in elementary functions – Dr. Sonnhard Graubner Jan 22 '17 at 15:51
• Sonnhard, It showed up in a calculation. I tried several substitutions did not work. – user91411 Jan 22 '17 at 15:56
• i send it to Wolfram Alpha – Dr. Sonnhard Graubner Jan 22 '17 at 16:02