関連ワード:  what is the derivative of sech x    what is the derivative of cosh x    what is the derivative of sech 2 x    what is the derivative of cosh 1 x    what is the derivative of cosh 2 x    what is the derivative of tanh x    what is the derivative of tanh inverse x    what is the derivative of tanh 1 x    what is the derivative of sec(x)