cosh^(2)x-sinh^(2)x=?

Prove that cosh^(4)x-sinh^(4)x=cosh2x

Prove that cosh(2x)-1=2sinh^(2)x

cosh^(4)(x)-sinh^(4)(x)=

Show that (cosh(2x)-1)/(sinh(2x)) = (sinh(2x))/(1+cosh(2x))=tanhx

int(sqrt(1-x^(2))+sqrt(1+x^(2)))/(sqrt(1-x^(4)))dx=(A)cosh^(-1)x+sin^(-1)x+c(B)cosh^(-1)x+cos^(-1)x+c(C)sinh^(-1)x+sin^(-1)x+c(D)sinh^(-1)x+cos^(-1)x+c

Cosh(2x) + sinh(2x) =

int(dx)/(sinh^(2)x cosh^(2)x)