Odpowiedź:
[tex]( {7}^{ \frac{1}{2} } - 4) ^{2} = 7 - 8 \times {7}^{ \frac{1}{2} } + 16 = \\ 7 - 8 \sqrt{7} + 16 = 23 - 8 \sqrt{7} [/tex]
[tex]( {4}^{ \frac{1}{2} } - {4}^{ - \frac{1}{2} } ) ^{2} = (( {2}^{2} ) {}^{ \frac{1}{2} } - \frac{1}{ {4}^{ \frac{1}{2} } } ) ^{2} = \\ (2 - \frac{1}{2} ) ^{2} = ( \frac{3}{2} ) ^{2} = \frac{9}{4} [/tex]
