Răspuns :
[tex]5 {}^{21} \times 5 \times 5 {}^{2} \\ 5 {}^{22} \times 5 {}^{2} \\ 5 {}^{24} [/tex]
[tex]5 {}^{21} \times 5 \times {5 }^{2} = [/tex]
[tex]5 {}^{21} \times 5 {}^{1} \times 5 {}^{2} = [/tex]
[tex]5 {}^{21 + 1 + 2} = [/tex]
[tex]5 {}^{24} [/tex]