=\(\dfrac{\left(\dfrac{7}{2^9}-\dfrac{14}{2^{11}}+\dfrac{21}{768}\right)^2}{\left(\dfrac{5}{2^9}-\dfrac{20}{2^{12}}+\dfrac{25}{1280}\right)^2}\)
= \(\dfrac{\left[7.\left(\dfrac{1}{2^9}-\dfrac{2}{2^{11}}+\dfrac{3}{768}\right)\right]^2}{\left[5.\left(\dfrac{1}{2^9}-\dfrac{4}{2^{12}}+\dfrac{5}{1280}\right)\right]^2}\)
=\(\dfrac{7^2}{5^2}\)