Find the cube of: (i) \(\frac{7}{9}\) (ii) \(\frac{-8}{11}\) (iii

1.	Find the cube of: (i) \(\frac{7}{9}\) (ii) \(\frac{-8}{11}\) (iii) \(\frac{12}{7}\) (iv) \(\frac{-13}{8}\)(v) \(2\frac{2}{5}\)
Answer» (i) \(\frac{7}{9}\) = \((\frac{7}{9})^3 = \) \(\frac{7^3}{9^3}\) = \(\frac{343}{729}\) (ii) \(-\frac{8}{11}\) = \((-\frac{8}{11})\) \( = -(\frac{8^3}{11^3})\) \( = -\frac{512}{1331}\) (iii) \(\frac{12}{7}\) = \((\frac{12^3}{7})\) = \(\frac{1728}{343}\) (iv) \(-\frac{13}{8}\) = \((-\frac{13^3}{8})\) = \(-(\frac{13^3}{8^3})\) = \(-\frac{2197}{512}\) (v) \(2\frac{2}{5}\) = \((2\frac{2}{5})^3\) = \((\frac{12}{5})^3\) = \(\frac{1728}{125}\)

Find the cube of: (i) \(\frac{7}{9}\) (ii) \(\frac{-8}{11}\) (iii) \(\frac{12}{7}\) (iv) \(\frac{-13}{8}\)(v) \(2\frac{2}{5}\)

Answer»

(i) \(\frac{7}{9}\)

= \((\frac{7}{9})^3 = \) \(\frac{7^3}{9^3}\) = \(\frac{343}{729}\)

(ii) \(-\frac{8}{11}\)

= \((-\frac{8}{11})\) \( = -(\frac{8^3}{11^3})\) \( = -\frac{512}{1331}\)

(iii) \(\frac{12}{7}\)

= \((\frac{12^3}{7})\) = \(\frac{1728}{343}\)

(iv) \(-\frac{13}{8}\)

= \((-\frac{13^3}{8})\) = \(-(\frac{13^3}{8^3})\) = \(-\frac{2197}{512}\)

(v) \(2\frac{2}{5}\)

= \((2\frac{2}{5})^3\) = \((\frac{12}{5})^3\) = \(\frac{1728}{125}\)