- #1

DryRun

Gold Member

- 838

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**Homework Statement**

Integral of sinhx.lncosh^2(x).dx

**The attempt at a solution**

I used integration by parts.

Let U = lncoshx^2(x)

Let dV = sinhx

So, dU =sech^2(x)/(2coshx.sinhx) = 1/(2cosh^3(x).sinhx) [i hope this line is correct?]

And, V = coshx

When using the formula for integration by parts, the integral of V.dU proves to be difficult. I think i should use substitution to simply it somehow, but not sure how.