Hi. Using trig sub to get integrals, I keep getting different but possibly equivalent answers as in book, and on calculator.

For example, integral(5/sqrt(25x^2-9),x)

By trig sub,

But, I am pretty sure I did the problem correctly.

I get: ln|5x/3+(5sqrt(x^2-9/25)/3|+c

Calculator gets: ln(sqrt(25x^2-9)+5x)

Wolfram integrator gets: log(2(sqrt(25x^2-9)+5x))

Are they equivalent? If they are, How can I show that they are to avoid my teacher marking off points?