$\"\"$

(a)

The expression is $\"\"$ .

Use the hyperbolic function : $\"\"$ .

$\"\"$

The numerical value of the expression $\"\"$ is $\"\"$ .

$\"\"$

(b)

The expression is $\"\"$ .

Definition of inverse hyperbolic functions : $\"\"$ .

Substitute $\"\"$ in the function $\"\"$ .

$\"\"$

The numerical value of the expression $\"\"$ is $\"\"$ .

$\"\"$

(a)

The numerical value of the expression $\"\"$ is $\"\"$ .

(b)

The numerical value of the expression $\"\"$ is $\"\"$ .