$\"\"$

\

(a).

\

The lens equation is $\"\"$ , \ \

\

where $\"\"$ is focal length.

\

$\"\"$ is distance from the lens to the image.

\

$\"\"$ is distance from the lens to the object.

\

Value of $\"\"$ , focal length is $\"\"$ .

\

Distance from the lens to the object, $\"\"$ is $\"\"$ .

\

Substiute the values of $\"\"$ and $\"\"$ in the equation $\"\"$ .

\

$\"\"$ .

\

\

(b).

\

Solve the value of $\"\"$ from the above equation.

\

$\"\"$

\

$\"\"$

\

Combine $\"\"$ using a common denominator.

\

By using the L.C.M the denominator obtained is $\"\"$ .

\

$\"\"$

\

Distance from the lens to the image is $\"\"$ cms.

\

$\"\"$

\

(a). The rational equation is $\"\"$ .

\

(b). Distance from the lens to the image is $\"\"$ cms.